Exposure method, exposure apparatus, and method for producing device

ABSTRACT

An exposure apparatus and method exposes a substrate by projecting an image of a pattern onto the substrate through a liquid. A projection optical system projects the image of the pattern onto the substrate. A recovery port recovers the liquid supplied onto the substrate. A temperature sensor measures a temperature of the liquid recovered via the recovery port.

CROSS-REFERENCE

This is a Division of U.S. patent application Ser. No. 12/222,706 filedAug. 14, 2008, which in turn is a Division of U.S. patent applicationSer. No. 11/287,317 filed Nov. 28, 2005 (now U.S. Pat. No. 7,483,117),which in turn is a Continuation of International Application No.PCT/JP2004/007569 filed May 26, 2004 claiming the conventional priorityof Japanese patent Application No. 2003-151369 filed on May 28, 2003.The disclosure of each of the prior applications is incorporated hereinby reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an exposure method, an exposureapparatus, and a method for producing a device wherein a substrate isexposed with a pattern in a state in which a liquid immersion area isformed between a projection optical system and the substrate.

2. Description of the Related Art

Semiconductor devices and liquid crystal display devices are produced bymeans of the so-called photolithography technique in which a patternformed on a mask is transferred onto a photosensitive substrate. Theexposure apparatus, which is used in the photolithography step, includesa mask stage for supporting the mask and a substrate stage forsupporting the substrate. The pattern on the mask is transferred ontothe substrate via a projection optical system while successively movingthe mask stage and the substrate stage. In recent years, it is demandedto realize the higher resolution of the projection optical system inorder to respond to the further advance of the higher integration of thedevice pattern. As the exposure wavelength to be used is shorter, theresolution of the projection optical system becomes higher. As thenumerical aperture of the projection optical system is larger, theresolution of the projection optical system becomes higher. Therefore,the exposure wavelength, which is used for the exposure apparatus, isshortened year by year, and the numerical aperture of the projectionoptical system is increased as well. The exposure wavelength, which isdominantly used at present, is 248 nm of the KrF excimer laser. However,the exposure wavelength of 193 nm of the ArF excimer laser, which isshorter than the above, is also practically used in some situations.When the exposure is performed, the depth of focus (DOF) is alsoimportant in the same manner as the resolution. The resolution R and thedepth of focus δ are represented by the following expressionsrespectively.

R=k ₁ ·λ/NA  (1)

δ=±k ₂ ·λ/NA ²  (2)

In the expressions, λ represents the exposure wavelength, NA representsthe numerical aperture of the projection optical system, and k₁ and k₂represent the process coefficients. According to the expressions (1) and(2), the following fact is appreciated. That is, when the exposurewavelength λ is shortened and the numerical aperture NA is increased inorder to enhance the resolution R, then the depth of focus δ isnarrowed.

If the depth of focus δ is too narrowed, it is difficult to match thesubstrate surface with respect to the image plane of the projectionoptical system. It is feared that the margin is insufficient during theexposure operation. Accordingly, the liquid immersion method has beensuggested, which is disclosed, for example, in International PublicationNo. 99/49504 as a method for substantially shortening the exposurewavelength and widening the depth of focus. In this liquid immersionmethod, the space between the lower surface of the projection opticalsystem and the substrate surface is filled with a liquid such as wateror any organic solvent so that the resolution is improved and the depthof focus is magnified about n times by utilizing the fact that thewavelength of the exposure light beam in the liquid is 1/n as comparedwith that in the air (n represents the refractive index of the liquid,which is about 1.2 to 1.6 in ordinary cases).

When a temperature distribution arises in the liquid, there has been apossibility to cause the change (for example, the inclination) of theimage plane of the image of the pattern to be formed on the substratethrough the liquid and the variation or fluctuation of variousaberrations including, for example, the distortion and themagnification.

SUMMARY OF THE INVENTION

The present invention has been made taking the foregoing circumstancesinto consideration, an object of which is to provide an exposure method,an exposure apparatus, and a method for producing a device wherein apattern can be accurately transferred when a substrate is subjected tothe liquid immersion exposure through a liquid disposed between aprojection optical system and the substrate.

In order to achieve the object as described above, the present inventionadopts the following constructions.

According to a first aspect of the present invention, there is providedan exposure method for exposing a substrate by projecting an image of apattern on a mask onto the substrate through a liquid disposed between aprojection optical system and the substrate, the exposure methodcomprising:

adjusting a projection state of the image of the pattern depending on adistribution of an exposure light beam which comes into the liquid; and

exposing the substrate in the adjusted projection state.

According to the present invention, even when any temperaturedistribution appears in the liquid as a result of the occurrence of anydistribution in the exposure light beam which comes into the liquiddisposed between the projection optical system and the substrate, theexposure condition, for example, the projection state of the image ofthe pattern is adjusted depending on the distribution of the exposurelight beam. Accordingly, the pattern can be transferred onto thesubstrate in a desired state. In this specification, the phrase“adjustment of the projection state of the image of the pattern” refersto not only the adjustment of the position of the image plane of theimage of the pattern but also the adjustment of the state of the imageof the pattern represented by the image formation characteristic such asthe magnification and/or the distortion of the image of the pattern. Theadjustment includes various types of adjustment in order to adjust theprojection state of the image of the pattern. The adjustment includesnot only the adjustment of the positional relationship between the imageplane of the image of the pattern and the exposure surface of thesubstrate and/or the adjustment of the projection optical system, butalso the adjustment of the wavelength of the exposure light beam, theadjustment (for example, the positional adjustment and the temperatureadjustment) and/or the exchange of the optical member disposed in theoptical path for the exposure light beam, the adjustment of the positionof the mask, and the adjustment or regulation of the atmosphere of theoptical path arriving at the substrate, including, for example, thetemperature, the pressure, and the gas concentration. Therefore, theadjustment also includes the change or the regulation of thetemperature, the flow rate, and the component of the liquid to besupplied to the space between the substrate and the projection opticalsystem.

According to a second aspect of the present invention, there is providedan exposure method for exposing a substrate by projecting an image of apattern on a mask onto the substrate through a liquid disposed between aprojection optical system and the substrate, the exposure methodcomprising:

adjusting a projection state of the image of the pattern depending on adistribution of the pattern on the mask; and

exposing the substrate in the adjusted projection state.

According to the present invention, even when any distribution arises inthe exposure light beam which comes into the liquid disposed between theprojection optical system and the substrate depending on thedistribution of the pattern on the mask, and any temperaturedistribution arises in the liquid thereby, then the pattern can betransferred onto the substrate in a desired state, for example, byadjusting the projection state of the image of the pattern depending onthe distribution of the pattern on the mask.

According to a third aspect of the present invention, there is providedan exposure method for exposing a substrate by projecting an image of apattern on a mask onto the substrate through a liquid disposed between aprojection optical system and the substrate, the exposure methodcomprising:

measuring information about a distribution of an exposure light beamwhich comes into the liquid via the projection optical system prior tothe exposure; and

exposing the substrate while adjusting a projection state of the imageof the pattern on the basis of the information about the measureddistribution.

According to the present invention, the information about thedistribution of the exposure light beam which comes into the liquid ispreviously measured to perform, for example, the adjustment of theprojection state of the image of the pattern during the exposure on thebasis of the result of the measurement. Accordingly, even when anydistribution arises in the exposure light beam which comes into theliquid, and the temperature of the liquid is partially changed, then thepattern can be transferred onto the substrate in a desired state whileaccurately adjusting the projection state of the image of the pattern.

According to a fourth aspect of the present invention, there is providedan exposure method for exposing a substrate by projecting an image of apattern onto the substrate by using a projection optical system whilemoving the substrate in a predetermined direction, the exposure methodcomprising:

measuring a temperature distribution of the liquid in a directionintersecting the predetermined direction;

adjusting a projection state of the image of the pattern on the basis ofinformation about the measured temperature distribution; and

exposing the substrate in the projection state of the image of thepattern.

According to the present invention, when the liquid immersion exposureis performed while moving the substrate, then the temperaturedistribution of the liquid is measured in the direction intersecting thedirection of movement of the substrate, and the projection state of theimage of the pattern is, for example, adjusted during the exposure onthe basis of the result of the measurement. Accordingly, even when thetemperature of the liquid is partially changed, then the projectionstate of the image of the pattern can be accurately adjusted, and theimage of the pattern can be transferred onto the substrate in a desiredstate.

According to a fifth aspect of the present invention, there is providedan exposure method for exposing a substrate by projecting an image of apattern on a mask onto the substrate through a liquid disposed between aprojection optical system and the substrate, the exposure methodcomprising:

measuring a temperature distribution of the liquid by using atemperature sensor arranged on a substrate stage which is movable whileholding the substrate; and

exposing the substrate on the substrate stage.

According to the present invention, the temperature distribution of theliquid which forms the liquid immersion area is directly measured byusing the temperature sensor arranged on the substrate stage.

Accordingly, the information about the temperature distribution of theliquid can be accurately determined. For example, the projection stateof the image of the pattern can be appropriately adjusted on the basisof the information about the measured temperature distribution of theliquid. The pattern can be transferred onto the substrate in a desiredstate.

As described above, the adjustment includes the adjustment of the imageformation characteristic of the projection optical system (adjustment ofthe optical characteristic), the adjustment of the positionalrelationship between the substrate and the image plane formed via theprojection optical system and the liquid, and the adjustment of thetemperature of the liquid for forming the liquid immersion area(adjustment of the temperature distribution).

According to a sixth aspect of the present invention, there is providedan exposure method for exposing a substrate by projecting an image of apattern onto the substrate through a liquid, the exposure methodcomprising:

setting an exposure condition depending on a temperature distribution ofthe liquid on the substrate onto which the image of the pattern isprojected; and

exposing the substrate under the set exposure condition.

According to a seventh aspect of the present invention, there isprovided an exposure apparatus which exposes a substrate by projectingan image of a predetermined pattern onto the substrate through a liquid,the exposure apparatus comprising:

a projection optical system which projects the image of the pattern ontothe substrate; and

a temperature sensor which is arranged movably in the vicinity of animage plane of the projection optical system and which measures atemperature of the liquid.

According to the present invention, the movable temperature sensor canbe used to directly measure the temperature and/or the temperaturedistribution of the liquid for forming the liquid immersion area.Therefore, for example, the projection state of the image of the patterncan be appropriately adjusted on the basis of the information about themeasured liquid temperature. The pattern can be transferred onto thesubstrate in a desired state.

According to an eighth aspect of the present invention, there isprovided an exposure apparatus which exposes a substrate by projectingan image of a predetermined pattern onto the substrate through a liquid,the exposure apparatus comprising:

a projection optical system which projects the image of the pattern ontothe substrate;

a substrate stage which moves the substrate in a predetermined directionduring the exposure; and

a temperature sensor which has a plurality of sensor elements arrangedwhile being separated from each other in a direction perpendicular tothe predetermined direction to measure a temperature of the liquid.

According to the present invention, the temperature distribution of theliquid in the direction intersecting the direction of movement of thesubstrate can be directly measured by using the plurality of sensorelements. Therefore, it is possible to accurately execute, for example,the adjustment of the projection state of the image of the patternduring the exposure on the basis of the information about the measuredtemperature of the liquid.

According to a ninth aspect of the present invention, there is providedan exposure apparatus which exposes a substrate by projecting an imageof a predetermined pattern onto the substrate through a liquid, theexposure apparatus comprising:

a projection optical system which projects the image of the pattern ontothe substrate; and

a liquid supply mechanism which is capable of supplying liquids havingmutually different temperatures from a plurality of positionsrespectively to form a liquid immersion area between the substrate andthe projection optical system.

According to the present invention, the liquid supply mechanism suppliesthe liquids having the mutually different temperatures from theplurality of positions respectively. Accordingly, the temperaturedistribution of the liquid in the liquid immersion area can be adjustedto be uniform. Therefore, it is possible to suppress of the occurrenceof the pattern deterioration which would be otherwise caused by anypartial change of the temperature of the liquid.

According to a tenth aspect of the present invention, there is providedan exposure apparatus which exposes a substrate by projecting an imageof a pattern onto the substrate through a liquid, the exposure apparatuscomprising:

a projection optical system which projects the image of the pattern ontothe substrate;

a sensor which measures a distribution of the pattern; and

a control unit which adjusts a projection state of the image of thepattern on the basis of the distribution of the pattern measured by thesensor.

According to an eleventh aspect of the present invention, there isprovided an exposure apparatus which exposes a substrate by projectingan image of a pattern onto the substrate through a liquid, the exposureapparatus comprising:

a projection optical system which projects the image of the pattern ontothe substrate;

a liquid recovery mechanism which recovers the liquid from thesubstrate; and

a temperature sensor which measures a temperature of the liquidrecovered by the liquid recovery mechanism.

According to a twelfth aspect of the present invention, there isprovided a method for producing a device, comprising using the exposuremethod as defined above. According to a thirteenth aspect of the presentinvention, there is provided a method for producing a device, comprisingusing the exposure apparatus as defined above. According to the presentinvention, it is possible to provide the device which has the patterntransferred at a satisfactory pattern transfer accuracy and which iscapable of exhibiting desired performance.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic arrangement illustrating a first embodiment ofan exposure apparatus of the present invention.

FIG. 2 shows a plan view illustrating a schematic arrangement of aliquid supply mechanism and a liquid recovery mechanism for constructinga part of the exposure apparatus of the present invention.

FIG. 3 shows a plan view illustrating a substrate stage for constructinga part of the exposure apparatus of the present invention.

FIG. 4 shows a flow chart illustrating an embodiment of an exposuremethod of the present invention.

FIG. 5 schematically illustrates a state in which the patterndistribution of a mask is measured.

FIG. 6 schematically illustrates a state in which a substrate issubjected to the liquid immersion exposure with a pattern of the mask.

FIG. 7 schematically illustrates a situation in which the position ofthe image plane, which is obtained via a projection optical system and aliquid, is changed depending on the temperature distribution of theliquid.

FIGS. 8A to 8C schematically show a procedure to determine thecorrection amount for correcting the change of the image plane positiondepending on the distribution of the exposure light beam.

FIG. 9 schematically shows another method for measuring the patterndistribution of the mask.

FIG. 10 shows a schematic arrangement illustrating a second embodimentof an exposure apparatus of the present invention.

FIG. 11 shows a schematic arrangement illustrating a third embodiment ofan exposure apparatus of the present invention.

FIG. 12 shows a schematic arrangement illustrating a fourth embodimentof an exposure apparatus of the present invention.

FIG. 13 shows a flow chart illustrating an embodiment of an exposuremethod of the present invention.

FIG. 14 shows a schematic arrangement illustrating a fifth embodiment ofan exposure apparatus of the present invention.

FIG. 15 shows a schematic arrangement illustrating a modified embodimentof FIG. 14.

FIG. 16 shows a flow chart illustrating exemplary steps of producing asemiconductor device.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

An explanation will be made below about embodiments of the exposureapparatus according to the present invention with reference to thedrawings. However, the present invention is not limited to theembodiments.

First Embodiment

FIG. 1 shows a schematic arrangement illustrating a first embodiment ofthe exposure apparatus of the present invention. With reference to FIG.1, an exposure apparatus EX principally includes a mask stage MST whichsupports a mask M, a substrate stage PST which supports a substrate P,an illumination optical system IL which illuminates, with an exposurelight beam EL, the mask M supported by the mask stage MST, a projectionoptical system PL which performs projection exposure for the substrate Psupported by the substrate stage PST with an image of a pattern of themask M illuminated with the exposure light beam EL, a control unit CONTwhich collectively controls the overall operation of the exposureapparatus EX, and a storage unit MRY which is connected to the controlunit CONT and which stores various pieces of information about theexposure operation including information about the distribution of thepattern MP of the mask M.

The exposure apparatus EX of this embodiment is a liquid immersionexposure apparatus to which the liquid immersion method is applied inorder that the exposure wavelength is substantially shortened to improvethe resolution and the depth of focus is substantially widened. Theexposure apparatus EX includes a liquid supply mechanism 10 whichsupplies the liquid 1 onto the substrate P, and a liquid recoverymechanism 30 which recovers the liquid 1 from the surface of thesubstrate P. In this embodiment, pure water is used for the liquid 1.The exposure apparatus EX forms a liquid immersion area AR2 on at leasta part of the substrate P including a projection area AR1 of theprojection optical system PL by the liquid 1 supplied from the liquidsupply mechanism 10 at least during the period in which the image of thepattern of the mask M is transferred onto the substrate P. Specifically,the exposure apparatus EX is operated as follows. That is, the spacebetween the surface (exposure surface) of the substrate P and an opticalelement 2 disposed at the end portion of the projection optical systemPL is filled with the liquid 1. The pattern image of the mask M isprojected onto the substrate P to expose the substrate P therewith viathe projection optical system PL and the liquid 1 disposed between theprojection optical system PL and the substrate P.

The embodiment of the present invention will now be explained asexemplified by a case of the use of the scanning type exposure apparatus(so-called scanning stepper) as the exposure apparatus EX in which thesubstrate P is exposed with the pattern MP formed on the mask M whilesynchronously moving the mask M and the substrate P in mutuallydifferent directions (opposite directions) in the scanning directions(predetermined direction). In the following explanation, the X axisdirection is the synchronous movement direction (scanning direction,predetermined direction) for the mask M and the substrate P in thehorizontal plane, the Y axis direction (non-scanning direction) is thedirection which is perpendicular to the X axis direction in thehorizontal plane, and the Z axis direction is the direction which isperpendicular to the X axis direction and the Y axis direction and whichis coincident with the optical axis AX of the projection optical systemPL. The directions about the X axis, the Y axis, and the Z axis aredesignated as θX, θY, and θZ directions respectively. The term“substrate” referred to herein includes those obtained by coating asemiconductor wafer surface with a photosensitive material such as aresist, and the term “mask” includes a reticle formed with a devicepattern to be subjected to the reduction projection onto the substrate.

The illumination optical system IL is used so that the mask M, which issupported on the mask stage MST, is illuminated with the exposure lightbeam EL. The illumination optical system IL includes, for example, anexposure light source, an optical integrator which uniformizes theilluminance of the light flux radiated from the exposure light source, acondenser lens which collects the exposure light beam EL emitted fromthe optical integrator, a relay lens system, and a variable fielddiaphragm which sets the illumination area (radiation area) IA on themask M illuminated with the exposure light beam EL to be slit-shaped.The predetermined illumination area IA on the mask M is illuminated withthe exposure light beam EL having a uniform illuminance distribution bythe illumination optical system IL. Those usable as the exposure lightbeam EL radiated from the illumination optical system IL include, forexample, emission lines (g-ray, h-ray, i-ray) in the ultraviolet regionradiated, for example, from a mercury lamp, far ultraviolet light beams(DUV light beams) such as the KrF excimer laser beam (wavelength: 248nm), and vacuum ultraviolet light beams (VUV light beams) such as theArF excimer laser beam (wavelength: 193 nm) and the F₂ laser beam(wavelength: 157 nm). In this embodiment, the ArF excimer laser beam isused. As described above, pure water is used for the liquid 1 in thisembodiment. Therefore, the exposure light beam EL is transmissivetherethrough even when the exposure light beam EL is the ArF excimerlaser beam. The emission line (g-ray, h-ray, i-ray) in the ultravioletregion and the far ultraviolet light beam (DUV light beam) such as theKrF excimer laser beam (wavelength: 248 nm) are also transmissivethrough pure water.

The mask stage MST supports the mask M. The mask stage MST istwo-dimensionally movable in the plane perpendicular to the optical axisAX of the projection optical system PL, i.e., in the XY plane, and it isfinely rotatable in the θZ direction. The mask stage MST is driven by amask stage-driving unit MSTD such as a linear motor. The maskstage-driving unit MSTD is controlled by the control unit CONT. Amovement mirror 50 is provided on the mask stage MST. A laserinterferometer 51 is provided at a position opposed to the movementmirror 50. The position in the two-dimensional direction and the angleof rotation of the mask M on the mask stage MST are measured inreal-time by the laser interferometer 51. The result of the measurementis outputted to the control unit CONT. The control unit CONT drives themask stage-driving unit MSTD on the basis of the result of themeasurement obtained by the laser interferometer 51 to thereby positionthe mask M supported on the mask stage MST.

The projection optical system PL projects the pattern on the mask M ontothe substrate P at a predetermined projection magnification β to performthe exposure. The projection optical system PL includes a plurality ofoptical elements including the optical element (lens) 2 provided at theend portion on the side of the substrate P. The optical elements forconstructing the projection optical system PL are supported by a barrelPK. The projection optical system PL is provided with an image formationcharacteristic control unit 3 which is capable of adjusting the imageformation characteristic (optical characteristic) of the projectionoptical system PL. The image formation characteristic control unit 3 isconstructed to include an optical element-driving mechanism which iscapable of moving a part of a plurality of optical elements forconstructing the projection optical system PL. A specified opticalelement, which is included in the plurality of optical elements forconstructing the projection optical system PL, can be moved in thedirection of the optical axis AX (Z direction) and/or inclined withrespect to the optical axis AX by the optical element-driving mechanism.The pressure of the space between the optical elements can be varied bythe image formation characteristic control unit 3. When the imageformation characteristic control unit 3 is controlled by using thecontrol unit CONT, it is possible to adjust the projection stateincluding various aberrations such as the projection magnification ofthe projection optical system PL and the distortion, and the image planeposition.

In this embodiment, the projection optical system PL is based on thereduction system having the projection magnification β which is, forexample, ¼ or ⅕. The projection optical system PL may be based on anyone of the 1× magnification system and the magnifying system. Theoptical element 2, which is disposed at the end portion of theprojection optical system PL of this embodiment, is provided detachably(exchangeably) with respect to the barrel PK. The optical element 2,which is disposed at the end portion, is exposed from the barrel PK. Theliquid 1 in the liquid immersion area AR2 makes contact with only theoptical element 2. Accordingly, the barrel PK formed of metal can beprevented from any corrosion or the like.

The optical element 2 is formed of fluorite. Fluorite has a highaffinity for water. Therefore, the liquid 1 is successfully allowed tomake tight contact with the substantially entire surface of a liquidcontact surface 2 a of the optical element 2. That is, in thisembodiment, the liquid (pure water) 1, which has the high affinity forthe liquid contact surface 2 a of the optical element 2, is supplied.Quartz having a high affinity for water may be used as the opticalelement 2 as well. A water-attracting (lyophilic or liquid-attracting)treatment may be applied to the liquid contact surface 2 a of theoptical element 2 to further enhance the affinity for the liquid 1.

The exposure apparatus EX further includes a focus-detecting system 4.The focus-detecting system 4 has a light-emitting section 4 a and alight-receiving section 4 b. The detecting light beam is projectedobliquely from an upper position onto the surface (exposure surface) ofthe substrate P via the liquid 1 from the light-emitting section 4 a.The reflected light beam therefrom is received by the light-receivingsection 4 b. The control unit CONT controls the operation of thefocus-detecting system 4. Further, the position (focus position) in theZ axis direction of the surface of the substrate P with respect to apredetermined reference surface is detected on the basis of alight-receiving (detection) result obtained by the light-receivingsection 4 b. Respective focus positions at a plurality of respectivepoints on the surface of the substrate P are determined, and thus thefocus-detecting system 4 also makes it possible to detect the posture ofthe substrate P in an inclined direction.

The substrate stage PST supports the substrate P. The substrate stagePST includes a Z stage 52 which holds the substrate P by the aid of asubstrate holder, an XY stage 53 which supports the Z stage 52, and abase 54 which supports the XY stage 53. The substrate stage PST isdriven by a substrate stage-driving unit PSTD such as a linear motor.The substrate stage-driving unit PSTD is controlled by the control unitCONT. It goes without saying that the Z stage and the XY stage may beprovided as an integrated body. When the XY stage 53 of the substratestage PST is driven, the substrate P is subjected to the control of theposition in the XY directions (position in the direction substantiallyparallel to the image plane of the projection optical system PL).

A movement mirror 55, which is movable together with the substrate stagePST with respect to the projection optical system PL, is provided on thesubstrate stage PST (Z stage 52). A laser interferometer 56 is providedat a position opposed to the movement mirror 55. The angle of rotationand the position in the two-dimensional direction of the substrate P onthe substrate stage PST are measured in real-time by the laserinterferometer 56. The result of the measurement is outputted to thecontrol unit CONT. The control unit CONT drives the XY stage 53 by theaid of the substrate stage-driving unit PSTD on the basis of the resultof the measurement of the laser interferometer 56 to thereby positionthe substrate P supported on the substrate stage PST in the X axisdirection and the Y axis direction.

The control unit CONT drives the Z stage 52 of the substrate stage PSTby the aid of the substrate stage-driving unit PSTD. Accordingly, thecontrol unit CONT controls the position (focus position) in the Z axisdirection of the substrate P held by the Z stage 52 and the position inthe θX direction and the θY direction. That is, the Z stage 52 isoperated on the basis of the instruction from the control unit CONTbased on the result of the detection performed by the focus-detectingsystem 4. The focus position (Z position) and the angle of inclinationof the substrate P are controlled so that the surface (exposure surface)of the substrate P is allowed to coincide with the image plane formedvia the projection optical system PL and the liquid 1.

An auxiliary plate 57 having a flat surface is provided on the substratestage PST (Z stage 52) so that the substrate P is surrounded thereby.The auxiliary plate 57 is installed so that the surface hasapproximately the same height as that of the surface of the substrate Pheld by the substrate holder. In this arrangement, a gap of about 1 to 2mm is provided between the auxiliary plate 57 and the edge of thesubstrate P. However, the liquid 1 scarcely flows into the gap owing tothe surface tension of the liquid 1. Even when the vicinity of thecircumferential edge of the substrate P is subjected to the exposure,the liquid 1 can be retained under the projection optical system PL bythe aid of the auxiliary plate 57.

The liquid supply mechanism 10 supplies the predetermined liquid 1 ontothe substrate P. The liquid supply mechanism 10 principally includes afirst liquid supply section 11 and a second liquid supply section 12which are capable of feeding the liquid 1, a first supply member 13which is connected to the first liquid supply section 11 via a supplytube 11A and which has a supply port for supplying, onto the substrateP, the liquid 1 fed (discharged) from the first liquid supply section11, and a second supply member 14 which is connected to the secondliquid supply section 12 via a supply tube 12A and which has a supplyport for supplying, onto the substrate P, the liquid 1 fed (discharged)from the second liquid supply section 12. The first and second supplymembers 13, 14 are arranged closely to the surface of the substrate P,and they are provided at mutually different positions in the surfacedirection of the substrate P. Specifically, the first supply member 13of the liquid supply mechanism 10 is provided on one side (−X side) inthe scanning direction with respect to the projection area AR1, and thesecond supply member 14 is provided on the other side (+X side) in thescanning direction so that the second supply member 14 is opposed to thefirst supply member 13.

Each of the first and second liquid supply sections 11, 12 includes, forexample, a tank for accommodating the liquid 1, and a pressurizing pump.The first and second liquid supply sections 11, 12 supply the liquid 1onto the substrate P via the supply tubes 11A, 12A and the supplymembers 13, 14 respectively. The operation of the first and secondliquid supply sections 11, 12 for supplying the liquid is controlled bythe control unit CONT. The control unit CONT is capable of controllingthe liquid supply amounts per unit time to be supplied onto thesubstrate P from the first and second liquid supply sections 11, 12independently respectively. Each of the first and second liquid supplysections 11, 12 includes a temperature-adjusting mechanism for theliquid. The liquid 1, which is adjusted to have approximately the sametemperature of 23° C. as the temperature in the chamber foraccommodating the apparatus therein, can be stably supplied onto thesubstrate P.

The liquid recovery mechanism 30 recovers the liquid 1 from the surfaceof the substrate P. The liquid recovery mechanism 30 includes first andsecond recovery members 31, 32 each of which has a recovery portarranged closely to the surface of the substrate P, and first and secondliquid recovery sections 33, 34 which are connected to the first andsecond recovery members 31, 32 via recovery tubes 33A, 34A respectively.Each of the first and second liquid recovery sections 33, 34 includes,for example, a sucking unit such as a vacuum pump, and a tank foraccommodating the recovered liquid 1. The first and second liquidrecovery sections 33, 34 recover the liquid 1 from the surface of thesubstrate P via the first and second recovery members 31, 32 and therecovery tubes 33A, 34A. The operation of each of the first and secondliquid recovery sections 33, 34 for recovering the liquid is controlledby the control unit CONT. The control unit CONT is capable ofcontrolling the liquid recovery amounts per unit time to be recovered bythe first and second liquid recovery sections 33, 34 independentlyrespectively.

FIG. 2 shows a plan view illustrating a schematic arrangement of theliquid supply mechanism 10 and the liquid recovery mechanism 30. Asshown in FIG. 2, the projection area AR1 of the projection opticalsystem (PL) is designed to have a slit shape (rectangular shape) inwhich the Y axis direction (non-scanning direction) is the longitudinaldirection. The liquid immersion area AR2, which is filled with theliquid 1, is formed on a part of the substrate P so that the projectionarea AR1 is surrounded thereby. As described above, the first supplymember 13 of the liquid supply mechanism 10, which is used to form theliquid immersion area AR2, is provided on one side (−X side) in thescanning direction with respect to the projection area AR1, and thesecond supply member 14 is provided on the other side (+X side) in thescanning direction on the opposite side. The first and second supplymembers 13, 14 are formed to be linear as viewed in a plan view in whichthe Y axis direction is the longitudinal direction respectively. Thesupply ports of the first and second supply members 13, 14 are formed tobe slit-shaped while the Y axis direction is the longitudinal directionrespectively, and they are directed to the surface of the substrate P.The liquid supply mechanism 10 simultaneously supplies the liquid 1 fromthe both sides in the X direction of the projection area AR1 from thesupply ports of the first and second supply members 13, 14. As describedabove, the liquid supply mechanism 10 of this embodiment is capable ofsupplying the liquid 1 onto the substrate (P) from a plurality ofpositions in a plurality of directions which are different from eachother with respect to the projection area AR1.

Each of the first and second recovery members 31, 32 of the liquidrecovery mechanism 30 has a recovery port which is formed continuouslyto be circular arc-shaped so that the recovery port is directed to thesurface of the substrate P. A substantially annular recovery port isformed by the first and second recovery members 31, 32 which arearranged so that they are opposed to one another. The respectiverecovery ports of the first and second recovery members 31, 32 arearranged to surround the projection area AR1 and the first and secondsupply members 13, 14 of the liquid supply mechanism 10. A plurality ofpartition members 35 are provided in the recovery port of each of thefirst and second recovery members 31, 32.

The liquid 1, which is supplied onto the substrate (P) from the supplyports of the first and second supply members 13, 14, is supplied so thatthe liquid 1 is spread while causing the wetting between the substrate(P) and the lower end surface of the end portion (optical element 2) ofthe projection optical system (PL). The liquid 1, which outflows to theoutside of the projection area AR1 and the first and second supplymembers 13, 14, is recovered from the recovery ports of the first andsecond recovery members 31, 32 arranged outside the first and secondsupply members 13, 14.

FIG. 3 shows a plan view illustrating the substrate stage PST. Anoptical sensor 20 as a photoelectric sensor is arranged at apredetermined position on the upper surface of the substrate stage PST(Z stage 52). In an exemplary embodiment shown in FIG. 3, the opticalsensor 20 is provided at the position other than the position of thesubstrate holder for holding the substrate P on the Z stage 52. Theoptical sensor 20 detects the optical information about the radiatedlight beam. Specifically, the optical sensor 20 detects the light amount(illuminance) of the radiated light beam. The detection signal of theoptical sensor 20 is outputted to the control unit CONT. The controlunit CONT determines the illuminance and the illuminance distribution ofthe radiated light beam on the basis of the result of the detectionperformed by the optical sensor 20. When the optical sensor 20 isarranged under the projection optical system PL by moving the substratestage PST, it is possible to detect the illuminance distribution of theexposure light beam EL allowed to pass through the projection opticalsystem PL.

The light-receiving surface (detection area) of the optical sensor 20has a size which is set to be equal to or larger than that of theprojection area AR1. Accordingly, the optical sensor 20 can receive allof the exposure light beam EL which passes through the mask M and whichpasses through the projection optical system PL. The optical sensor 20is provided so that the position of the light-receiving surface thereofin the Z axis direction is coincident with the position in the Z axisdirection of the image plane (image formation plane) of the projectionoptical system PL. The optical sensor 20 has a plurality oflight-receiving surfaces which are arranged in the non-scanningdirection (Y axis direction). The plurality of light-receiving surfacescan be used to measure the illuminance independently respectively.Therefore, the output values of the illuminances measured by theplurality of light-receiving surfaces express the illuminancedistribution of the exposure light beam EL in the non-scanning directionas they are.

The substrate stage PST is moved to effect the positional adjustmentbetween the optical sensor 20 and the projection area AR1 of theprojection optical system PL. Further, as shown in FIG. 1, the mask M isplaced on the mask stage MST, and the mask M is illuminated with thepredetermined illumination area IA by using the exposure light beam EL.Accordingly, the optical sensor 20 is irradiated with the exposure lightbeam EL allowed to pass through the mask M and the projection opticalsystem PL. The mask M has a chromium pattern MP which serves as alight-shielding section. Therefore, the exposure light beam EL isradiated onto the optical sensor 20 in accordance with the illuminancedistribution corresponding to the pattern MP of the mask M.

As described above, the optical sensor 20 detects the illuminancedistribution in the Y axis direction of the exposure light beam EL to beradiated. The control unit CONT determines the information about thepattern distribution of the mask M in the Y axis direction in theillumination area IA on the basis of the detection result obtained bythe optical sensor 20.

Next, an explanation will be made with reference to a flow chart shownin FIG. 4 about a method for exposing the substrate P with the patternimage of the mask M by using the exposure apparatus EX as describedabove. In this procedure, the exposure apparatus EX of this embodimentprojects the pattern image of the mask M onto the substrate P to performthe exposure while moving the mask M and the substrate P in the X axisdirection (scanning direction). During the scanning exposure, thepattern image of a part of the mask M corresponding to the illuminationarea IA is projected onto the slit-shaped (rectangular) projection areaAR1 disposed just under the end portion of the projection optical systemPL. In this procedure, the mask M is moved at the velocity V in the −Xdirection (or in the +X direction) with respect to the projectionoptical system PL, in synchronization with which the substrate P ismoved at the velocity β·V (β represents the projection magnification) inthe +X direction (or in the −X direction) by the aid of the XY stage 53.A plurality of shot areas (SA) are established on the substrate P. Thesubstrate P is subjected to the stepping movement after the completionof the exposure for one shot area (SA), and the next shot area (SA) onthe substrate is moved to the scanning start position. After that, thescanning exposure process is successively performed for the respectiveshot areas SA while moving the substrate P in accordance with thestep-and-scan manner.

The illuminance distribution of the exposure light beam EL is measuredas follows in a state in which the mask M is not placed on the maskstage MST prior to the liquid immersion exposure process for producingthe device. The control unit CONT allows the illumination optical systemIL to radiate the exposure light beam EL, and the control unit CONTcontrols the illumination optical system IL and the substrate stage PSTso that the exposure light beam EL, which has passed through theprojection optical system PL, is received by the optical sensor 20disposed on the substrate stage PST. In this way, the illuminancedistribution of the exposure light beam EL is measured on the substratestage PST (on the side of the image plane of the projection opticalsystem PL). Accordingly, the illuminance (reference illuminance) of theexposure light beam EL is determined on the side of the image plane ofthe projection optical system PL without passing through the mask M. Themeasured reference illuminance is stored in the storage unit MRY.

Subsequently, the mask M is loaded on the mask stage MST. The controlunit CONT determines the illuminance distribution of the exposure lightbeam EL allowed to pass through the mask M and the projection opticalsystem PL, on the side of the image plane of the projection opticalsystem PL by using the optical sensor 20 in a state in which the mask Mis placed on the mask stage MST. FIG. 5 schematically shows a state inwhich the illuminance distribution of the exposure light beam EL allowedto pass through the mask M and the projection optical system PL ismeasured by using the optical sensor 20. As shown in FIG. 5, the controlunit CONT moves the substrate stage PST to perform the positionaladjustment between the optical sensor 20 and the projection area AR1 ofthe projection optical system PL. The exposure light beam EL is radiatedfrom the illumination optical system IL in this state. Accordingly, theexposure light beam EL, which has passed through the mask M and theprojection optical system PL, is radiated onto the optical sensor 20. InFIG. 5, the density of the chromium pattern (light-shielding section) MPis high in an approximately half area on the +Y side in the pattern areaPA on the mask M. Such a density distribution is provided at anyposition in the X direction in the pattern area PA. In this situation,the illumination area (radiation area) IA of the exposure light beam ELon the mask M is set to have a slit shape extending in the Y axisdirection in the pattern area PA on the mask M. The both ends thereof inthe Y axis direction are positioned on the light-shielding band SB. Thepartial pattern, which is included in the illumination area IA on themask M, is projected onto the projection area AR1 of the projectionoptical system PL. The optical sensor 20 receives the exposure lightbeam EL depending on the pattern distribution in the illumination areaIA. The control unit CONT determines the illuminance distribution in theY axis direction, i.e., the incident energy distribution in the Y axisdirection of the exposure light beam EL coming into the liquid 1 forforming the liquid immersion area AR2 during the liquid immersionexposure, on the basis of the result of the detection performed by theoptical sensor 20.

Further, the control unit CONT controls the illumination optical systemIL and the substrate stage PST and moves the mask stage MST forsupporting the mask M in the X axis direction with respect to theexposure light beam EL while radiating the exposure light beam EL ontothe illumination area IA on the mask M. Accordingly, the exposure lightbeam EL is successively radiated onto the entire surface of the patternarea PA of the mask M. In this situation, the optical sensor 20(substrate stage PST) is not moved. The position of the mask M (maskstage MST) is measured by the laser interferometer 51. The control unitCONT determines the illuminance distribution of the exposure light beamEL at the respective positions in the scanning direction (X direction)of the mask M on the basis of the result of the measurement of theposition of the mask M in the X axis direction measured by the laserinterferometer 51 and the result of the detection performed by theoptical sensor 20 for the exposure light beam EL allowed to pass throughthe illumination area IA of the mask M in this situation. Accordingly,the control unit CONT determines the information about the illuminancedistribution of the exposure light beam EL allowed to pass through theprojection optical system PL (Step S1).

Subsequently, the control unit CONT determines the pattern distribution(density distribution of the pattern) of the mask M on the basis of theilluminance information (reference illuminance) of the exposure lightbeam EL detected without passing through the mask M and the illuminanceinformation of the exposure light beam EL detected via the mask M (StepS2). The illuminance distribution of the exposure light beam EL allowedto pass through the mask M and the projection optical system PLcorresponds to the pattern distribution of the mask M. Therefore, thecontrol unit CONT can determine the pattern distribution of the mask Mby subtracting the amount corresponding to the illuminance distributionof the reference illuminance from the illuminance distribution of theexposure light beam EL detected via the mask M. The information aboutthe determined pattern distribution of the mask M is stored in thestorage unit MRY.

Subsequently, the control unit CONT estimates (calculates) theinformation about the temperature change of the liquid 1 in the liquidimmersion area AR2 during the liquid immersion exposure on the basis ofthe exposure amount (illuminance on the substrate P) to be set duringthe liquid immersion exposure in order to produce the device, theinformation about the determined pattern distribution of the mask M, andthe liquid immersion exposure condition. Specifically, the control unitCONT determines the change of the temperature distribution of the liquidin the liquid immersion area AR2 (Step S3). In this procedure, theliquid immersion exposure condition (parameter) includes the movementvelocity of the substrate P, the material characteristic such as thespecific heat of the liquid 1, and the liquid supply amount (flow rate)per unit time to be supplied from the liquid supply mechanism 10. Therelationship between the liquid temperature change amount (distribution)and the pattern distribution of the mask M corresponding to theparameter is previously stored in the storage unit MRY. The control unitCONT estimates (calculates) the liquid temperature distribution on thebasis of the stored relationship. The relationship can be previouslydetermined, for example, by means of an experiment or simulation. In thefollowing explanation, the liquid temperature change amount and theliquid temperature distribution will be collectively and appropriatelyreferred to as “liquid temperature distribution information”. The liquidrecovery amount per unit time to be recovered by the liquid recoverymechanism 30 may be added as the parameter.

Subsequently, the control unit CONT determines the change distributionand the change amount of the image characteristic including the changeof the image plane position to be obtained via the projection opticalsystem PL and the liquid 1 on the basis of the determined liquidtemperature distribution information (Step S4). In the followingexplanation, the change amount and the change distribution of the imagecharacteristic will be collectively and appropriately referred to as“image characteristic change information”.

An explanation will now be made with reference to FIGS. 6 and 7 aboutthe temperature change of the liquid 1 disposed between the projectionoptical system PL and the substrate P depending on the distribution ofthe pattern MP on the mask M. FIG. 6 schematically shows a state inwhich the liquid immersion exposure is performed with the pattern MP ofthe mask M via the projection optical system PL and the liquid 1 in theliquid immersion area AR2. FIG. 7 schematically shows the temperaturedistribution of the liquid. The liquid 1 is omitted from theillustration in FIG. 6 for the convenience of explanation. As shown inFIG. 6, when an approximately half portion of the pattern area PA on themask M is an area in which the density of the chromium pattern MP ishigh, a larger amount of the exposure light beam EL comes into the otherhalf of the projection area AR1 as compared with one half of theprojection area AR1 on the substrate P, because the light transmittanceis low in the high density area. Accordingly, the light amountdistribution (illuminance distribution) arises for the exposure lightbeam EL coming into the liquid 1 disposed between the projection opticalsystem PL and the substrate P depending on the pattern distribution ofthe mask M. Further, as shown in FIG. 7, the temperature inclination(change of the temperature distribution) in the Y axis direction arisesin the liquid 1 as depicted by a dotted line. The temperature change ofthe liquid 1 causes the change of the refractive index of the liquid 1.Therefore, the situation shown in FIG. 7 brings about the change of theimage plane such that the inclination is principally caused about the Xaxis, depending on the temperature change of the liquid 1. That is, theangle of refraction, which is obtained when the light beam comes intothe liquid and passes through the liquid, also exhibits the dependencyon the temperature, because the refractive index of the liquid changesdepending on the temperature of the liquid. As a result, the image isdistorted (the image is partially contracted or expanded in the Ydirection).

In view of the above, the control unit CONT determines the informationabout the temperature distribution of the liquid 1 on the basis of thedistribution of the pattern on the mask M as well as the distribution ofthe exposure light beam EL which comes into the liquid 1 disposedbetween the projection optical system PL and the substrate P toapproximate or estimate the image characteristic change (for example,the change of the position of the image plane) on the basis of theinformation about the determined temperature distribution.

The control unit CONT determines the correction amount (correctioninformation) to correct the image characteristic on the basis of thedetermined image characteristic change information (Step S5). Anexplanation will now be made with reference to FIG. 8 about an exemplaryprocedure for determining the correction amount. The followingexplanation will be made about a case in which the position of the imageplane formed via the projection optical system PL and the liquid 1 ischanged depending on the change of the temperature distribution of theliquid 1, in order to simplify the explanation. For example, as shown inFIG. 8A, it is assumed that the illuminance distribution in the Y axisdirection of the projection area AR1 of the projection optical system PLis provided as follows. That is, the exposure amount (illuminance) isconstant until arrival at a certain position in the +Y direction, theexposure amount is thereafter increased to a predetermined value, andthen the exposure amount is constant at the predetermined value. On thisassumption, the image plane, which is formed via the projection opticalsystem PL and the liquid 1, is similarly in a state as shown in FIG. 8Bdepending on the temperature distribution as well. Accordingly, thecontrol unit CONT divides the determined image characteristic changecomponent (image plane position change component) into a plurality ofcomponents, i.e., the 0-order component as the offset component, the1st-order component as the inclination component, and the higher-ordercomponent as shown in FIG. 8C. Further, the control unit CONT determinesthe correction amounts for the respective components respectively. Thecorrection amounts can be used to perform the correction by controllingthe exposure apparatus as follows. For example, as for the 0-ordercomponent and the 1st-order component concerning the change of the imageplane, the positional relationship between the surface of the substrateP and the image plane formed via the projection optical system PL andthe liquid 1 is corrected by correcting the driving (posture) of thesubstrate stage PST. The higher-order component is corrected by drivingthe image formation characteristic control unit 3 of the projectionoptical system PL. In this embodiment, the projection area AR1 has theslit shape extending in the Y axis direction. Therefore, in order toadjust the position of the substrate stage PST during the scanningexposure, it is enough to principally perform the positional adjustment(focus adjustment) in relation to the Z axis direction and the tiltadjustment (rolling adjustment) in the θX direction. Of course, when thewidth of the projection area AR1 in the X axis direction is large, thetilt adjustment (pitching adjustment) in the θY direction is performedduring the scanning exposure in order to make the position of the imageplane to coincide with the position of the surface of the substrate. Thecontrol unit CONT stores, in the storage unit MRY, the correctionamounts (correction information) corresponding to the position of themask M in the scanning direction (X axis direction).

After the determination of the correction amount in order to makecoincidence between the positions of the surface of the substrate P andthe image plane formed via the projection optical system PL and theliquid 1, the control unit CONT performs the liquid immersion exposureprocess (Step S6) while adjusting the posture of the substrate P(inclination of the substrate P, position in the Z axis direction) onthe basis of the correction amount determined as described above. Thatis, as shown in FIG. 1, the control unit CONT uses the substratetransport system to load the substrate P on the substrate stage PST, andthen the control unit CONT drives the liquid supply mechanism 10 tostart the liquid supply operation for supplying the liquid onto thesubstrate P. The liquid 1, which is fed from the first and second liquidsupply sections 11, 12 respectively in order to form the liquidimmersion area AR2, is supplied onto the substrate P through the supplytubes 11A, 12A and the first and second supply members 13, 14 to formthe liquid immersion area AR2 between the projection optical system PLand the substrate P. In this situation, the supply ports of the firstand second supply members 13, 14 are arranged on the both sides in the Xaxis direction (scanning direction) of the projection area AR1. Thecontrol unit CONT executes the control to simultaneously supply theliquid 1 onto the substrate P on the both sides of the projection areaAR1 from the supply ports of the liquid supply mechanism 10.Accordingly, the liquid 1, which is supplied onto the substrate P,forms, on the substrate P, the liquid immersion area AR2 in a rangewider than at least the projection area AR1.

In this embodiment, when the liquid 1 is supplied to the substrate Pfrom the both sides in the scanning direction of the projection areaAR1, the control unit CONT controls the liquid supply operation of thefirst and second liquid supply sections 11, 12 of the liquid supplymechanism 10 so that the liquid supply amount per unit time, which is tobe supplied from the side in front of the projection area AR1 inrelation to the scanning direction, is set to be larger than the liquidsupply amount to be supplied from the side opposite thereto. Forexample, when the exposure process is performed while moving thesubstrate P in the +X direction, the control unit CONT performs thesetting so that the liquid amount from the −X side with respect to theprojection area AR1 (i.e., from the supply ports 13A) is larger than theliquid amount from the +X side (i.e., from the supply ports 14A). On theother hand, when the exposure process is performed while moving thesubstrate P in the −X direction, the control unit CONT performs thesetting so that the liquid amount from the +X side with respect to theprojection area AR1 is larger than the liquid amount from the −X side.

Further, the control unit CONT controls the first and second liquidrecovery sections 33, 34 of the liquid recovery mechanism 30 to performthe liquid recovery operation for recovering the liquid 1 from thesurface of the substrate P concurrently with the supply operation forsupplying the liquid 1 by the liquid supply mechanism 10. Accordingly,the liquid 1 on the substrate P, which is supplied from the supply portsof the first and second supply members 13, 14 and which outflows to theoutside of the projection area AR1, is recovered from the recovery portsof the first and second recovery members 33, 34. As described above, theliquid recovery mechanism 30 can efficiently recover the liquid 1 fromthe surface of the substrate P through the recovery ports, because therecovery ports are provided to surround the projection area AR1.

The control unit CONT performs the liquid immersion exposure whilecontrolling the relationships of the inclination and the position in theZ axis direction between the substrate P and the image plane by the aidof the image formation characteristic control unit 3 and the substratestage-driving unit PSTD on the basis of the correction informationstored in the storage unit MRY and the result of the detection of theposition information of the surface of the substrate P detected by thefocus-detecting system 4.

Accordingly, even when the image plane position is changed depending onthe change of the pattern distribution of the mask M, i.e., the changeof the temperature distribution of the liquid 1 depending on thedistribution of the exposure light beam EL which comes into theprojection area AR1, it is possible to perform the scanning exposure forthe shot area (SA) on the substrate P while substantially makingcoincidence between the surface of the substrate P (exposure surface)and the image plane formed via the projection optical system PL and theliquid 1. Accordingly, it is possible to accurately form the desiredpattern on the substrate P.

As explained above, the adjustment is performed for the projectionstate, which includes, for example, the adjustment for the posture andthe position of the substrate P during the liquid immersion scanningexposure and the adjustment for the position of the image plane of theprojection optical system PL based on the use of the image formationcharacteristic control unit so that the desired pattern image isprojected onto the substrate P on the basis of the distributioninformation of the pattern MP of the mask M. Accordingly, it is possibleto perform the accurate pattern transfer.

The exemplary embodiment shown in FIGS. 6 and 7 is illustrative of thecase in which the pattern distribution in the illumination area IA onthe mask M is not changed so much as the mask M is moved. However, inordinary cases, the pattern distribution in the illumination area IA ofthe exposure light beam EL on the mask M is changed as the mask M ismoved. In such circumstances, the distribution of the exposure lightbeam EL which comes into the projection area AR1 (liquid 1) is changedas the mask M is moved. The temperature distribution of the liquid 1 ischanged due to the change of the distribution of the exposure light beamEL. Therefore, the position of the image plane is also changed dependingon the temperature distribution of the liquid 1. Therefore, it is fearedthat the pattern image to be projected onto the substrate P may bedeteriorated.

However, in this embodiment, the control unit CONT stores the correctioninformation corresponding to the position of the mask M in the scanningdirection (X axis direction). The correction information is readdepending on the position of the mask M (depending on the result of themeasurement performed by the laser interferometer 51) during theexposure for the shot area SA on the substrate P. Therefore, the surfaceof the substrate P (exposure surface) can be correctly adjusted to matchthe image plane.

In this embodiment, when the pattern distribution of the mask M in thenon-scanning direction (Y axis direction) is changed only slightly, itis also allowable to consider only the change of the patterndistribution in the illumination area IA caused by the movement of themask M, i.e., the change of the intensity of the exposure light beam ELwhich comes into the liquid 1. In this case, the control unit CONTdetermines the totalized value (totalized light amount distribution)obtained by totalizing the illuminance distribution in the Y axisdirection (longitudinal direction) of the projection area AR1 measuredby the optical sensor 20 in relation to the X axis direction. Thecalculated totalized value is determined while corresponding the valueto the position of the mask M in the X axis direction. Accordingly, itis possible to determine the change of the pattern distribution in theillumination area IA caused by the movement of the mask M.

In this embodiment, depending on the change of the image plane caused bythe temperature change of the liquid 1, the surface position of thesubstrate P is adjusted, and the position of the image plane is adjustedby moving a part of the optical element of the projection optical systemPL and/or varying the pressure of the space between the optical elementsby the aid of the image formation characteristic control unit. However,it is also allowable to perform any one of the adjustment of the surfaceposition of the substrate P and the adjustment of the position of theimage plane. Alternatively, the image plane position may be adjusted bymoving the position of the mask M with the mask stage MST and/or finelyadjusting the wavelength of the exposure light beam. The adjustment ofthe image plane position can be also achieved by moving and/orexchanging a part of the optical member of the illumination opticalsystem IL. Further alternatively, it is also allowable to adjust thetemperature of the optical member (including the projection opticalsystem PL) disposed in the optical path for the exposure light beam EL.

In this embodiment, the explanation has been made about the correctionof the change of the image plane caused by the change of the temperature(distribution) of the liquid 1. However, the present invention is notlimited to only the change of the image plane. When the image formationcharacteristic such as the magnification and the distortion is changedon the basis of the temperature distribution of the liquid 1, the imageformation characteristic of the pattern image may be also adjusteddepending on the distribution information of the pattern MP of the maskM (i.e., the distribution of the exposure light beam EL which comes intothe liquid 1). The adjustment of the image formation characteristic canbe achieved by moving a part of the optical element of the projectionoptical system PL and/or adjusting the pressure of the space between theoptical elements in the same manner as in the adjustment of the positionof the image plane. Alternatively, the adjustment of the image formationcharacteristic can be also achieved by moving the mask M and/or finelyadjusting the wavelength of the exposure light beam EL. Furtheralternatively, the adjustment of the image formation characteristic canbe also achieved by moving and/or exchanging a part of the opticalmember of the illumination optical system IL. Further alternatively, itis also allowable to adjust the temperature of the optical member(including the projection optical system PL) disposed in the opticalpath for the exposure light beam EL. Further alternatively, it is alsoallowable to adjust the state of the polarization of the exposure lightbeam EL and/or the state of the wavefront, when the image formationcharacteristic is adjusted.

In this embodiment, when the position is adjusted for the surface of thesubstrate P and the image plane formed via the projection optical systemPL and the liquid 1 during the liquid immersion scanning exposure, theinformation about the surface position of the substrate P is detected bythe focus-detecting system 4, and the substrate stage PST is driven onthe basis of the result of the detection performed by thefocus-detecting system 4 to adjust the position and the posture of thesubstrate P. In this case, the detecting light beam, which is radiatedobliquely from the upper position onto the surface of the substrate Pfrom the light-emitting section 4 a of the focus-detecting system 4,passes through the liquid 1. However, there is such a possibility thatthe refractive index may be changed depending on the temperature changeof the liquid 1, and any error may arise in the detected value of thefocus for the surface of the substrate P. In such a situation, thestorage unit MRY previously stores the relationship between thetemperature (temperature change amount) and the refractive index(refractive index change amount) of the liquid 1 to determine therefractive index of the liquid 1 on the basis of the relationship andthe information about the temperature change of the liquid 1 determinedin Step S3. On condition that the thickness of the liquid 1 isconsidered, the detected value of the focus is corrected on the basis ofthe determined refractive index. Accordingly, even when the temperatureof the liquid 1 is change, it is possible to determine the informationabout the surface position of the substrate P. Therefore, it is possibleto adjust and match the image plane and the surface of the substrate Pmore correctly. Alternatively, the adjustment amount of the positionalrelationship between the image plane and the substrate surface, which isbased on the detected value of the focus-detecting system 4, may becorrected on the basis of the relationship between the refractive indexand the temperature of the liquid 1 stored in the storage unit MRY.

The measurement of the pattern distribution of the mask M as describedabove and the determination of the image characteristic changeinformation and the liquid temperature distribution information based onthe result of the measurement may be performed at least every time whenthe mask M is changed. However, even when the mask M is not changed, themeasurement and the determination as described above may be performedperiodically. Further, the pattern distribution information of the maskM may be stored in the storage unit MRY. Accordingly, when thepredetermined mask M is used, then the mask M is once unloaded, and thenthe mask M is used again, the measurement of the pattern distribution ofthe mask M may be omitted, and the pattern distribution informationstored in the storage unit MRY may be used as it is.

In this embodiment, the pattern distribution information of the mask Mis determined. However, the change of the temperature distribution ofthe liquid may be determined by using the illuminance distributioninformation measured by the optical sensor 20 as it is. In this case,the temperature of the liquid 1 is changed depending on variousparameters including, for example, the pattern density of the mask M,the output of the exposure light source, the liquid supply amount (orthe flow rate) per unit time for forming the liquid immersion area AR2,and the specific heats of the liquid and the substrate P. It is enoughthat the storage unit MRY previously stores, as a data table, therelationship between the illuminance distribution and the liquidtemperature change amount while considering the parameters as describedabove. The relationship between the illuminance distribution and theliquid temperature change amount may be verified by previouslyperforming an experiment. In the case of the liquid immersion exposureapparatus in which the type of the liquid 1 for forming the liquidimmersion area AR2 is changeable, the storage unit MRY may previouslystore data tables corresponding to the respective liquids.

It is considered that the temperature of the liquid 1 arranged betweenthe projection optical system PL and the substrate P is changeddepending on the reflected light beam of the exposure light beam ELreflected by the surface of the substrate P. In such a case, thereflectance of the surface of the substrate P may be used as oneparameter of the data table.

In this embodiment, after the mask M is placed on the mask stage MST,the distribution information of the exposure light beam EL is measuredvia the projection optical system PL by using the optical sensor 20provided on the substrate stage PST, and the distribution of the patternMP of the mask M is measured on the basis of the result of themeasurement. However, for example, the following procedure is alsoavailable. That is, the pattern distribution information of the mask M(for example, the density and the transmittance of the mask at each ofthe positions of the mask) is determined from the designed value. Theobtained value is stored in the storage unit MRY. When the liquidimmersion scanning exposure is performed, the temperature change and/orthe change of the temperature distribution of the liquid 1 isapproximated or estimated while considering the stored distributioninformation. The adjustment of the projection state such as theadjustment of the image characteristic and/or the adjustment of thesubstrate position is performed on the basis of the result of theapproximation or estimate.

Alternatively, as shown in FIG. 9, a pattern-measuring unit 60 formeasuring the pattern distribution of the mask M may be provided at aposition different from the mask stage MST. As shown in FIG. 9, thepattern-measuring unit 60 includes a light-emitting section 61 which isprovided over the mask M supported by a support section 66 and whichradiates the measuring light beam onto the mask M, and a light-receivingsection 62 which is provided below the mask M and which receives thelight beam transmitted through the mask M on the basis of the measuringlight beam radiated on the mask M. The measuring light beam is radiatedfrom the light-emitting section 61 while relatively moving the mask M inthe X axis direction with respect to the light-emitting section 61 andthe light-receiving section 62. The light-receiving section 62 receivesthe transmitted light through the mask M while making synchronousmovement together with the light-emitting section 61. Accordingly, thetransmitted light beam of the measuring light beam is received for theentire surface of the pattern area PA of the mask M. In thisarrangement, the following arrangement may be adopted for the relativemovement of the mask M and the light-emitting section 61 and thelight-receiving section 62. That is, the mask M may be moved in the Xaxis direction together with the support section 66 in a state in whichthe positions of the light-emitting section 61 and the light-receivingsection 62 are fixed. Alternatively, the light-emitting section 61 andthe light-receiving section 62 may be synchronously moved in the X axisdirection in a state in which the position of the mask M is fixed.Further alternatively, both of the mask M and the light-emitting section61 and the light-receiving section 62 may be moved oppositely to oneanother in the X axis direction.

The result of the measurement performed by the light-receiving section62 is outputted to the control unit CONT. The control unit CONTdetermines the pattern distribution of the mask M on the basis of theresult of the measurement performed by the light-receiving section 62(pattern-measuring unit 60). The information about the pattern densityof the mask M measured by the pattern-measuring unit 60 is stored in thestorage unit MRY. When the liquid immersion scanning exposure isperformed, the adjustment of the image characteristic and the adjustmentof the substrate position (adjustment of the projection state) areperformed on the basis of the correction information determined from thestored pattern distribution.

It is considered that a situation arises such that the illuminancedistribution of the exposure light beam EL which arrives at thesubstrate stage PST (on the side of the image plane of the projectionoptical system PL) via the projection optical system PL and the mask Msupported by the mask stage MST does not correspond to the pattern(pattern distribution) of the mask M. However, even in such a situation,the pattern can be satisfactorily transferred to the substrate P bydirectly determining the change of the temperature distribution of theliquid and performing the adjustment of the image characteristic and/orthe adjustment of the posture of the substrate P, in place of thedetermination of the pattern distribution of the mask from theilluminance distribution measured by the optical sensor 20 disposed onthe substrate stage PST as described above.

The optical sensor 20 used in this embodiment has a plurality oflight-receiving surfaces in the non-scanning direction. However, theilluminance distribution of the exposure light beam EL may be determinedby moving an optical sensor 20 having a small light-receiving surface inthe X axis direction, in the Y axis direction, or in both of the X axisdirection and the Y axis direction by the substrate stage PST.

Second Embodiment

Next, an explanation will be made about a second embodiment of theexposure apparatus of the present invention with reference to FIG. 10.In this embodiment, the projection state is adjusted by making theadjustment so that any temperature distribution is not generated in theliquid 1 of the liquid immersion area AR2 depending on the patterndistribution of the mask M (distribution of the exposure light beam ELwhich comes into the projection area AR1), i.e., so that the temperaturedistribution of the liquid 1 is uniformized. In particular, theadjustment is made so that the temperature distribution is uniform inthe Y axis direction as the direction perpendicular to the scanningdirection (X axis direction). This embodiment is constructed in the samemanner as the first embodiment except for the liquid supply mechanism.In the following explanation, the constitutive portions, which are thesame as or equivalent to those of the first embodiment described above,are designated by the same reference numerals, any explanation of whichwill be simplified or omitted.

With reference to FIG. 10, a liquid supply mechanism 50 includes a firstliquid supply section 51 and a second liquid supply section 52. Firstends of a plurality of supply tubes 51 a, 51 b, 51 c, 51 d, 51 e, 51 fare connected to the first liquid supply section 51. A plurality ofsupply ports 53 a, 53 b, 53 c, 53 d, 53 e, 53 f, which are arranged inthe non-scanning direction (Y axis direction) and which are disposedclosely to the substrate P, are provided at second ends of the supplytubes 51 a to 51 f, respectively. Similarly, first ends of a pluralityof supply tubes 52 a, 52 b, 52 c, 52 d, 52 e, 52 f are connected to thesecond liquid supply section 52. A plurality of supply ports 54 a, 54 b,54 c, 54 d, 54 e, 54 f, which are arranged in the non-scanning direction(Y axis direction) and which are disposed closely to the substrate P,are provided at second ends of the supply tubes 52 a to 52 f,respectively. The supply ports 53 a to 53 f, 54 a to 54 f of the liquidsupply mechanism 50 are provided in a plurality of directions withrespect to (the center of) the projection area AR1 while being separatedtherefrom by different distances. In this embodiment, the supply ports53 a to 53 f, 54 a to 54 f are arranged and aligned in the Y axisdirection respectively, and the supply ports supply the liquid 1 from aplurality of positions separated from each other in the Y axis directionrespectively.

The first and second liquid supply sections 51, 52 are provided with aplurality of temperature-adjusting mechanisms which are connected to therespective supply tubes 51 a to 51 f, 52 a to 52 f. The liquid 1 can besupplied onto the substrate P from the respective supply ports 53 a to53 f, 54 a to 54 f at mutually different temperatures respectively. Thatis, the liquid supply mechanism 50, which supplies the liquid 1 onto thesubstrate P in order to form the liquid immersion area AR2 in thisembodiment, is capable of supplying the liquid 1 from the plurality ofpositions at mutually different temperatures respectively. The liquid 1is supplied at the plurality of positions. The temperature of the liquid1 is successfully allowed to differ depending on the liquid supplypositions, i.e., the respective positions of the supply ports 53 a to 53f, 54 a to 54 f. The supply ports 53 a to 53 f, 54 a to 54 f are capableof supplying the liquid 1 at the mutually different temperatures fromthe plurality of positions separated from each other in the Y axisdirection as the direction perpendicular to the X axis direction as thescanning direction respectively.

In this embodiment, the liquid 1 is not supplied simultaneously fromboth of the first liquid supply section 51 and the second liquid supplysection 52. The first liquid supply section 51 and the second liquidsupply section 52 are used while being switched depending on thescanning direction of the substrate P. That is, when the scanningexposure is performed while moving the substrate P in the +X direction,the first liquid supply section 51 is operated to supply the liquid fromthe supply ports 53 a to 53 f. When the scanning exposure is performedwhile moving the substrate P in the −X direction, the second liquidsupply section 52 is operated to supply the liquid from the supply ports54 a to 54 f.

The operation of the liquid supply mechanism 50 is controlled by thecontrol unit CONT. The storage unit MRY previously stores theinformation about the pattern distribution of the mask M. As describedabove, the distribution of the exposure light beam EL which comes intothe liquid 1 disposed between the projection optical system PL and thesubstrate P is also changed depending on the pattern distribution of themask M. In this embodiment, the control unit CONT controls thetemperature of the liquid to be supplied from each of the supply ports53 a to 53 f (or 54 a to 54 f) of the liquid supply mechanism 50 on thebasis of the information about the pattern distribution of the mask M.

For example, when the shot area SA on the substrate P is subjected tothe scanning exposure while moving the substrate P in the +X direction,then the liquid 1, which has approximately the same temperature of 23°C. as the temperature in the chamber, is supplied from the supply ports53 d, 53 e, 53 f, and the liquid, which has a temperature lower thanthat of the liquid supplied from the supply ports 53 d, 53 e, 53 f, issupplied from the supply ports 53 a, 53 b, 53 c, while considering thepattern distribution of the mask M (distribution of the exposure lightbeam EL which comes into the liquid 1). Accordingly, even when thedistribution (illuminance distribution) of the incoming exposure lightbeam EL is deviated (see, for example, FIG. 8A), the projection statecan be adjusted by uniformizing the temperature distribution of theliquid 1 through which the exposure light beam EL passes. Therefore, theimage of the pattern of the mask M can be accurately projected onto thesubstrate P.

Next, an explanation will be made with reference to FIG. 10 about amethod for adjusting the projection state by uniformizing thetemperature of the liquid in the liquid immersion area. At first, thedistribution of the exposure light beam EL which comes into the liquid 1is previously determined (Step 1) as explained with reference to FIG. 4,before performing the liquid immersion exposure. Further, the patterndistribution of the mask M is determined (Step S2), and the temperaturedistribution of the liquid 1 is determined (Step S3). In this case, inStep S3, the temperature distribution information of the liquid 1 in theY axis direction (non-scanning direction) as the direction intersectingthe scanning direction (X axis direction) is especially determined. Thecontrol unit CONT adjusts the temperature of the liquid to be suppliedfrom each of the respective supply ports 53 a to 53 f on the basis ofthe determined liquid temperature distribution information. Accordingly,it is possible to uniformize the temperature of the liquid 1 for formingthe liquid immersion area AR2 especially in the Y axis direction.Further, it is possible to avoid the deterioration of the pattern imagewhich would be otherwise caused by the temperature distribution of theliquid.

In this embodiment, the temperature of the liquid 1 to be supplied ontothe substrate P is adjusted to uniformize the temperature of the liquid1 between the projection optical system PL and the substrate P. However,the temperature distribution of the liquid 1 of the liquid immersionarea AR2 may be uniformized by allowing any non-exposing light beam (forexample, any infrared ray not photosensitizing the resist) to come intoa portion at which the exposure light beam scarcely incomes so that theliquid disposed at the portion is heated.

In this embodiment, when the adjustment (adjustment for the projectionstate) is performed for the image which is projected onto the substratedepending on the pattern distribution of the mask M, it is alsoallowable to combine the adjusting method of this embodiment and theadjusting method of the first embodiment. For example, the 0-ordercomponent of the image plane position change explained with reference toFIG. 8 is corrected by adjusting the position of the surface of thesubstrate P by using the substrate stage PST. The 1st-order component ofthe image plane position change is corrected by adjusting the imagecharacteristic of the projection optical system PL by using, forexample, the image formation characteristic control unit 3. Thehigher-order component of the image plane position change is correctedby adjusting the temperature of the liquid to be supplied from each ofthe plurality of supply ports 53 a to 53 f respectively.

This embodiment is constructed such that the liquid temperaturedistribution in the non-scanning direction of the liquid immersion areaAR2 is uniformized by mutually changing the temperature of the liquid 1to be supplied from each of the respective supply ports 53 a to 53 f.However, for example, the liquid temperature distribution in thenon-scanning direction of the liquid immersion area AR2 can be alsouniformized by changing the supply amounts of the liquid to be suppliedper unit time from the respective supply ports 53 a to 53 frespectively. In this case, the increase in the temperature of theliquid is suppressed at places corresponding to larger supply amounts ofthe liquid per unit time. On the contrary, the increase in thetemperature of the liquid is facilitated at places corresponding tosmaller supply amounts of the liquid per unit time. When the pressure,which is applied to the substrate P by the liquid 1 for forming theliquid immersion area AR2, is changed depending on the supply amount ofthe liquid to be supplied from the respective supply ports 53 a to 53 f,and any error arises in the positional adjustment between the surface ofthe substrate P and the image formation plane of the pattern image, thenthe positional relationship between the surface of the substrate P andthe image formation plane of the pattern image may be correcteddepending on the supply amount of the liquid to be supplied from therespective supply ports 53 a to 53 f. In this embodiment, the liquidtemperature distribution in the non-scanning direction of the liquidimmersion area AR2 is uniformized by mutually changing the temperatureof the liquid 1 to be supplied from each of the respective supply ports53 a to 53 f. However, the temperature of the liquid 1 to be suppliedfrom each of the respective supply ports 53 a to 53 f can be alsoadjusted respectively so that the liquid temperature distribution in thenon-scanning direction of the liquid immersion area AR2 is nonuniform inorder that the projection state of the pattern image is adjusted to be adesired state.

This embodiment is constructed such that the liquid 1 is supplied fromone side in the X axis direction (scanning direction) with respect tothe projection area AR1 of the projection optical system PL. However,the liquid 1 may be supplied from both sides in the X axis direction(scanning direction) in relation to the projection area AR1.Alternatively, one or more liquid supply ports may be provided on oneside or both sides in the Y axis direction (non-scanning direction) tosupply the liquid 1 in the X axis direction and the Y axis direction.Further alternatively, a plurality of such liquid supply ports may beprovided to supply the liquid at different temperatures from therespective supply ports.

Third Embodiment

Next, an explanation will be made with reference to FIG. 11 about athird embodiment of the exposure apparatus EX of the present invention.In this embodiment, the liquid supply mechanism and the liquid recoverymechanism are changed as follows. As shown in FIG. 11, the exposureapparatus EX includes a liquid supply mechanism 10 which has two supplytubes 71, 72 (supply ports 71A, 72A) provided and aligned in the Z axisdirection as the direction perpendicular to the X axis direction, and aliquid recovery mechanism 30 which has two recovery tubes 73, 74(recovery ports 74A, 74A) provided and aligned in the Z axis directionso that the recovery tubes 73, 74 are opposed to the supply tubes 71,72. The liquid supply mechanism 10 is capable of supplying the liquidfrom the respective supply ports 71A, 72A at mutually differenttemperatures. Accordingly, two liquid layers LQ1, LQ2, which havetemperatures different from each other, can be formed in the liquidimmersion area AR2.

When the liquid is supplied in accordance with the method as describedabove, for example, the following situation is obtained. That is, theliquid 1, which is supplied in order to form the liquid layer LQ1 as theupper layer to make contact with the optical element 2 disposed at theend portion of the projection optical system PL, can be always suppliedat an approximately constant temperature. The liquid 1, which isincluded in the liquid layer LQ2 as the lower layer to make contact withthe surface of the substrate P that tends to undergo the increase in thetemperature by being irradiated with the exposure light beam EL, can besupplied while changing the temperature of the liquid 1 depending on thepattern distribution of the mask M (distribution of the incomingexposure light beam). When the liquid 1, which is supplied in order toform the liquid layer LQ1 as the upper layer, is always adjusted to havethe substantially constant temperature, it is possible to suppress thetransfer of the thermal change caused by the heat generated by thesubstrate P to the optical element 2 disposed at the end portion of theprojection optical system PL. The liquid, which is supplied in order toform the liquid layer LQ2 as the lower layer, may have a temperaturewhich is lower than the temperature of the liquid supplied in order toform the liquid layer LQ1 as the upper layer. Of course, the temperatureof the liquid 1 for forming the liquid layer LQ1 as the upper layer maybe changed depending on the pattern distribution of the mask M(distribution of the incoming exposure light beam). The temperature ofthe liquid to be supplied from the respective supply ports 71A, 72A maybe adjusted so that the temperature of the liquid of the liquid layerLQ1 as the upper layer is approximately the same as the temperature ofthe liquid of the liquid layer LQ2 as the lower layer, or thetemperature may be adjusted so that any temperature difference appears.

In this embodiment, the two supply tubes and the two recovery tubes areprovided in the Z axis direction respectively. However, three or more orany arbitrary number of supply tubes and recovery tubes may be arrangedand aligned in the Z axis direction respectively. Accordingly, theliquid supply mechanism 10 can supply the liquid 1 from a plurality ofpositions, separated from each other in the Z axis direction, atmutually different temperatures. FIG. 11 merely shows one set of thesupply tubes 71, 72 and the recovery tubes 73, 74 separated from eachother in the X axis direction. However, a plurality of sets of supplytubes and recovery tubes may be arranged and aligned in the Y axisdirection. Also in this embodiment, it is possible to bring aboutdifferent supply amounts of the liquid supplied per unit time from therespective supply ports 71A, 72A respectively. In this case, it ispossible to provide different supply amounts for the supply port 71A andthe supply port 72A so that the temperature of the liquid of the liquidlayer LQ1 is the same as the temperature of the liquid of the liquidlayer LQ2, or a desired difference in temperature appears. It is alsopossible to provide different supply amounts for the supply port 71A andthe supply port 72A so that the velocity of the flow of the liquid ofthe liquid layer LQ1 is approximately the same as the velocity of theflow of the liquid of the liquid layer LQ2, or a desired difference invelocity appears.

Fourth Embodiment

Next, an explanation will be made with reference to FIG. 12 about afourth embodiment of the exposure apparatus EX of the present invention.This embodiment is constructed such that a temperature-measuring unit(sensor) for measuring the temperature of the liquid as described belowis provided, and first and second liquid supply sections are used asliquid recovery mechanisms. As shown in FIG. 12, the exposure apparatusEX includes a temperature sensor 81 which has a plurality of sensorelements 81 a to 81 f separated from each other in the Y axis directionand a temperature sensor 82 which has sensor elements 82 a to 82 f, tomeasure the temperature of the liquid. The sensor elements 81 a to 81 fare provided on supply tubes 51 a to 51 f respectively. The sensorelements 82 a to 82 f are provided on supply tubes 52 a to 52 frespectively.

The first liquid supply section 51 and the second liquid supply section52 of this embodiment function as the liquid recovery mechanisms forrecovering the liquid 1 from the surface of the substrate Prespectively. That is, the first and second liquid supply sections 51,52 are capable of sucking and recovering the liquid 1 from the surfaceof the substrate P by the aid of supply ports and supply tubes. Forexample, the second liquid supply section 52 functions as the liquidrecovery mechanism to recover the liquid 1 from the surface of thesubstrate P during the period in which the first liquid supply section51 supplies the liquid 1 onto the substrate P. When the recovered liquid1 passes through the supply tubes (recovery tubes) 52 a to 52 f, thetemperature is measured by the sensor elements 82 a to 82 f. In otherwords, the liquid 1 can be recovered from the surface of the substrate Pby the aid of the recovery ports (supply ports) 54 a to 54 e provided ata plurality of positions separated from each other in the Y axisdirection, of the second liquid supply section 52 which functions as theliquid recovery mechanism, and the temperature of the liquid 1 recoveredat a plurality of positions can be measured by the plurality of sensorelements 82 a to 82 f respectively. Similarly, the first liquid supplysection 51 functions as the liquid recovery mechanism to recover theliquid 1 from the surface of the substrate P during the period in whichthe second liquid supply section 52 supplies the liquid 1 onto thesubstrate P. When the recovered liquid 1 flows through the supply tubes(recovery tubes) 51 a to 51 f, the temperature is measured by the sensorelements 81 a to 81 f.

Next, an explanation will be made with reference to a flow chart shownin FIG. 13 about a procedure of the liquid immersion exposure based onthe use of the exposure apparatus EX shown in FIG. 12. At first, themask M is loaded on the mask stage MST, and the substrate P is loaded onthe substrate stage PST. Subsequently, the control unit CONT drives theliquid supply mechanism 50 and the liquid recovery mechanism 30respectively to form the liquid immersion area AR2 between theprojection optical system PL and the substrate P. Subsequently, the maskM is illuminated with the exposure light beam EL to perform the testexposure for the substrate P (Step SB1). The liquid 1 of the liquidimmersion area AR2 is irradiated with the exposure light beam EL in onlyan area which corresponds to the slit-shaped projection area AR1 havingthe longitudinal direction as the Y axis direction. Therefore, thetemperature distribution is principally generated in the Y axisdirection. In this procedure, a test substrate, which is different fromthe substrate for producing the device, may be used as the substrate P.

For example, when the liquid is supplied by the second liquid supplysection 52 in order to perform the liquid immersion exposure whilemoving the substrate P in the −X direction, the first liquid supplysection 51 functions as the liquid recovery mechanism. Accordingly, theliquid 1 on the substrate P is recovered by the aid of the recoverytubes (supply tubes) 51 a to 51 f. The temperature of the liquid flowingthrough each of the recovery tubes 51 a to 51 f respectively is measuredby the sensor elements 81 a to 81 f, respectively. The results of thetemperature measurement performed by the respective sensor elements 81 ato 81 f are outputted to the control unit CONT. The control unit CONTdetermines the temperature distribution of the liquid 1 in the Y axisdirection on the basis of the respective results of the detectionperformed by the plurality of sensor elements 81 a to 81 f aligned inthe Y axis direction (Step SB2). The first liquid supply section 51,which functions as the liquid recovery mechanism in this procedure, isconstructed so that an amount of the liquid, with which the liquidtemperature can be measured, is recovered.

The control unit CONT determines the correction amounts for thetemperature of the liquid to be supplied from each of the respectivesupply ports 54 a to 54 f connected to the second liquid supply section52 on the basis of the liquid temperature distribution determined inStep SB2 so that the desired pattern image is projected onto thesubstrate P via the projection optical system PL and the liquid 1, i.e.,the temperature of the liquid 1 in the liquid immersion area AR2 isuniform in the Y axis direction (Step SB3).

Subsequently, the control unit CONT performs the liquid immersionexposure (hereinafter referred to as “production exposure”) to actuallyproduce the device while adjusting the temperature of the liquid 1 to besupplied onto the substrate P from each of the supply ports 54 a to 54 fon the basis of the determined correction amounts for the liquidtemperature (Step SB4). The first liquid supply section 51 does notfunction as the liquid recovery section (function is canceled) duringthe production exposure.

On the other hand, when the exposure is performed while moving thesubstrate P in the +X direction, the second liquid supply section 52functions as the liquid recovery mechanism. The test exposure and theproduction exposure are performed in accordance with the same procedureas the procedure described above.

In this embodiment, the following procedure is adopted as the method foradjusting the projection state. That is, the temperature distribution ofthe liquid 1 is determined (Step SB2), and then the temperature of theliquid 1 to be supplied is adjusted so that the desired pattern image isprojected onto the substrate P. However, it is also allowable toperform, for example, the adjustment of the supply amount of the liquid1 per unit time, the adjustment of the position and the posture of thesubstrate P, and/or the adjustment of the image characteristic of theprojection optical system PL as described above. It is also allowable toperform the various adjustment processes in combination. In thisembodiment, the temperature of the liquid to be supplied from each ofthe respective supply ports are adjusted on the basis of the results ofthe detection performed by the plurality of sensor elements 81 a to 81 fso that the temperature of the liquid 1 in the liquid immersion area AR2is uniform. However, the correction amounts of the temperature of theliquid to be supplied from each of the respective supply ports may bedetermined after analyzing the pattern formed on the substrate P by thetest exposure. In this procedure, the temperature of the liquid to besupplied from each of the respective supply ports may be adjusted sothat the temperature of the liquid 1 in the liquid immersion area AR2 isnonuniform.

Fifth Embodiment

Next, an explanation will be made with reference to FIG. 14 about afifth embodiment of the exposure apparatus EX of the present invention.This embodiment is constructed such that the temperature distribution ofthe liquid is determined by using a dummy substrate. As shown in FIG.14, a plurality of temperature sensors 90 are provided on the surface ofthe dummy substrate DP. The dummy substrate DP has approximately thesame size and the same shape as those of the substrate P for producingthe device. The dummy substrate DP can be arranged on (can be held by)the substrate stage PST as a movable member which is movable whileholding the substrate P. The dummy substrate DP is detachable withrespect to the substrate stage PST. That is, the temperature sensors 90on the dummy substrate DP are also detachable with respect to thesubstrate stage PST.

The temperature sensor 90 has a plurality of sensor elements 91 providedon the surface of the dummy substrate DP. The sensor element 91 isconstructed of, for example, a thermocouple.

A plurality of sensor arrangement areas SC, which correspond to the shotareas SA (see FIG. 6), are set on the dummy substrate DP. The sensorarrangement areas SC are designed to have approximately the same sizes(shapes) and the same arrangement as those of the shot areas SA to beexposed with the device pattern respectively. In this embodiment, threesensor arrangement areas SC in the X axis direction and the Y axisdirection respectively (3×3), i.e., nine sensor arrangement areas SC intotal are established substantially in a matrix form.

The plurality of sensor elements 91 are arranged for each of the sensorarrangement areas SC in a matrix form as viewed in a plan viewrespectively. In this embodiment, five sensor elements 91 in the X axisdirection and the Y axis direction (5×5), i.e., twenty-five sensorelements 91 in total are provided in one sensor arrangement area SCrespectively. That is, the temperature sensor 90 on the dummy substrateDP has the plurality of sensor elements 91 which are separated from eachother at least in the non-scanning direction (Y axis direction) of thesubstrate P (dummy substrate DP).

A detecting section (probe) of the sensor element 91 of the temperaturesensor 90 is exposed on the surface of the dummy substrate DP, which iscapable of detecting the temperature of the liquid 1 in the liquidimmersion area AR2. When the dummy substrate DP provided with thetemperature sensors 90 is held by the substrate stage PST, thetemperature sensors 90, which measure the temperature of the liquid 1 inthe liquid immersion area AR2, can be arranged movably in the vicinityof the image plane of the projection optical system PL.

The sensor elements 91, which are arranged in the shot area SA includingthe projection area AR1 of the projection optical system PL, arearranged in the projection area AR1 of the projection optical system PLand the vicinity thereof. When the plurality of sensor elements 91 arearranged in the non-scanning direction (Y axis direction) in relation tothe projection area AR1, it is possible to measure the temperaturedistribution at least in the non-scanning direction (Y axis direction)of the projection area AR1.

Signal transmission lines (cables) 93, which feed the temperaturedetection signals of the sensor elements 91 (temperature sensors 90) tothe control unit CONT, are connected to the respective sensorarrangement areas SC. First ends of the signal transmission lines areconnected to the sensor elements 91 (temperature sensors 90) of therespective sensor arrangement areas SC. Second ends of the signaltransmission lines are connected to the control unit CONT disposedoutside the dummy substrate DP (outside the substrate stage PST). Thesignal transmission lines 93 are embedded in the dummy substrate DP. Thesignal transmission lines 93, which are led out from the end of thedummy substrate DP, are connected to the control unit CONT.

The respective sensor arrangement areas SC, which are provided on thesurface of the dummy substrate DP, are subjected to the surfacetreatment so that they have mutually different light reflectances.Specifically, the respective sensor arrangement areas SC are coated withmaterial films which have mutually different light reflectancesrespectively. Accordingly, when the exposure light beam EL is radiatedvia the projection optical system PL and the liquid 1, the sensorelements 91 (temperature sensors 90), which are arranged in therespective sensor arrangement areas SC, can measure the temperature ofthe liquid 1 under mutually different light reflection conditions.

Alignment marks 94, which are formed to perform the positionaladjustment of the sensor arrangement areas SC with respect topredetermined positions, are provided for the respective sensorarrangement areas SC on the dummy substrate DP. The alignment marks 94are detected by an unillustrated alignment system. The alignment systemdetermines the position information of the projection area AR1 of theprojection optical system PL with respect to the temperature sensors 90(sensor elements 91) arranged in the sensor arrangement areas SC on thebasis of the results of the detection of the positions of the alignmentmarks 94. Subsequently, the alignment marks 94 are used to effect thepositional adjustment between the projection area AR1 of the projectionoptical system PL and the sensor elements 91 of the respective sensorarrangement areas SC. Specifically, the process of positional adjustmentis performed so that the sensor elements 91, which are aligned in thenon-scanning direction (Y axis direction) and which are included in thesensor elements 91 arranged in the matrix form in the sensor arrangementarea SC, are arranged in the projection area AR1 of the projectionoptical system PL, i.e., the direction of the alignment of the pluralityof sensor elements 91 in the Y axis direction is coincident with thelongitudinal direction of the projection area AR1 of the projectionoptical system PL.

Next, an explanation will be made about a procedure for measuring thetemperature of the liquid 1 in the liquid immersion area AR2 with thetemperature sensors 90 shown in FIG. 14. Before performing the liquidimmersion exposure process for producing the device, the mask M isfirstly loaded on the mask stage MST, and the dummy substrate DPprovided with the temperature sensors 90 as described above is loaded onthe substrate stage PST. Subsequently, the control unit CONT detects thepositions of the alignment marks 94 as described above to determine thepositional relationship between the projection area AR1 of theprojection optical system PL and the temperature sensors 90 of thesensor arrangement areas SC so that the longitudinal direction (Y axisdirection) of the projection area AR1 is coincident with the alignmentdirection of the sensor elements 91 in relation to the Y axis direction.Subsequently, the control unit CONT drives the liquid supply mechanism50 and the liquid recovery mechanism 30 respectively to form the liquidimmersion area AR2 between the projection optical system PL and thedummy substrate DP, and the mask M is irradiated with the exposure lightbeam EL. When the exposure light beam EL, which has passed through themask M and the projection optical system PL, is radiated onto the liquid1, the temperature distribution, which is caused by the illuminancedistribution of the exposure light beam EL, arises in the liquid 1. Thecontrol unit CONT measures the temperature distribution of the liquid 1in the liquid immersion area AR2 by using the temperature sensors 90arranged on the substrate stage PST while performing the scanningmovement in the X axis direction for the mask stage MST which supportsthe mask M and the substrate stage PST which supports the dummysubstrate DP, in the same manner as in the operation to be performedwhen the device is produced. The temperature distribution of the shotarea SA (projection area AR1) in the Y axis direction as well as thepattern distribution in the Y axis direction of the mask M is measuredon the basis of the results of the detection of the respective sensorelements 91 aligned in the Y axis direction. On the other hand, thetemperature distribution of the shot area SA in the X axis direction aswell as the pattern distribution in the X axis direction of the mask Mis measured on the basis of the respective results of the detection ofthe plurality of sensor elements 91 provided in the X axis direction inthe sensor arrangement area SC to be subjected to the scanning movementin the X axis direction with respect to the projection area AR1.Accordingly, it is possible to measure the temperature distribution ofthe liquid 1 in the XY directions for one shot area SA.

In this procedure, the control unit CONT measures the temperaturedistribution for the plurality of sensor arrangement areas SCestablished on the dummy substrate DP respectively. The sensorarrangement areas SC are designed so that the light reflectances aredifferent from each other respectively. Therefore, for example, when thesubstrate P, which has any different light reflectance (specifically anydifferent type of photoresist), is used during the device production, itis possible to measure the liquid temperature distribution informationunder the light reflection direction corresponding to each of thesubstrates P.

The control unit CONT can execute various operations as described aboveso that the desired pattern image is projected onto the substrate P viathe projection optical system PL and the liquid 1 on the basis of thetemperature information (temperature distribution information) of theliquid 1 measured by using the temperature sensors 90 provided on thedummy substrate DP. For example, the correction amount is determined forcorrecting the driving operation of the image formation characteristiccontrol unit 3, and the correction amount is determined for correctingthe movement (posture) of the substrate stage PST during the scanningexposure. Further, the correction amount is determined for correctingthe temperature of the liquid to be supplied from each of the supplyports 54 a to 54 f (53 a to 53 f) (see FIG. 10) so that the temperatureof the liquid 1 in the liquid immersion area AR2 is uniform as in thesecond embodiment described above. The determined correction amounts arestored in the storage unit MRY.

The dummy substrate DP is unloaded from the substrate stage PST, and thesubstrate P for producing the device is loaded on the substrate stagePST during the period in which the control unit CONT performs theprocess for determining the correction amount as described above.Subsequently, the control unit CONT adjusts the temperature of theliquid 1 to be supplied for forming the liquid immersion area AR2 on thebasis of the determined correction amount, adjusts the imagecharacteristic of the projection optical system PL, and/or adjusts themovement (posture) of the substrate stage PST. Accordingly, the liquidimmersion scanning exposure is performed for the substrate P whileadjusting the positional relationship between the surface of thesubstrate P and the image plane formed via the projection optical systemPL and the liquid 1.

FIG. 15 shows another embodiment of the dummy substrate DP provided withthe temperature sensors 90. As shown in FIG. 15, a storage element 95,which stores the temperature detection signals of the temperaturesensors 90, is provided for the dummy substrate DP. Specifically, thestorage element 95 is embedded in the dummy substrate DP.

When the temperature of the liquid 1 of the liquid immersion area AR2 isdetected by using the dummy substrate DP shown in FIG. 15, then thetemperature of the liquid 1 of the liquid immersion area AR2 is detectedin a state in which the dummy substrate DP is held by the substratestage PST, and the result of the detection is stored in the storageelement 95. Subsequently, after performing the test exposure, the dummysubstrate DP is unloaded from the substrate stage PST, and thetemperature detection result stored in the storage element 95 isextracted (read). When the liquid immersion exposure process isperformed in order to produce the device, the control unit CONTdetermines the correction amount for adjusting the image characteristicof the projection optical system PL and/or determines the correctionamount for adjusting the temperature of the liquid 1 to form the liquidimmersion area AR2 on the basis of the extracted temperature informationof the liquid in the same manner as in the embodiment described above.The storage element 95 may be provided detachably with respect to thedummy substrate DP. The storage element 95 may be detached from thedummy substrate DP after detecting the temperature of the liquid 1 toextract the result of the detection of the liquid temperature stored inthe storage element 95.

As explained above, the liquid temperature can be measured whileperforming the scanning movement with respect to the exposure light beamEL by arranging the substrate having the temperature sensors 90 providedon the movable substrate stage PST. Therefore, it is possible to measurethe liquid temperature distribution of the liquid immersion area AR2corresponding to the shot area SA for producing the device. Owing to theconstruction that the temperature sensors 90 are provided on the dummysubstrate DP having substantially the same shape as that of thesubstrate P for producing the device, the temperature can be measured inthe state in which the liquid immersion area AR2 is satisfactorilyformed between the projection optical system PL and the dummy substrateDP, i.e., under substantially the same condition as the liquid immersionexposure condition to be adopted during the production of the device.Further, the temperature of the liquid 1 can be accurately adjustedduring the liquid immersion exposure on the basis of the result of themeasurement.

As described above, the temperature distribution of the liquid immersionarea AR2 is principally caused by the radiation of the exposure lightbeam EL. However, it is considered that the temperature distribution isalso caused, for example, by the temperature environment around theexposure apparatus (around the liquid immersion area). In such asituation, when the temperature of the liquid is directly measured bythe temperature sensors 90 as in this embodiment, the liquid temperaturedistribution of the liquid immersion area AR2 can be accurately measuredeven when the temperature environment around the exposure apparatus isvaried.

In this embodiment, the temperature sensors 90 for detecting thetemperature of the liquid 1 in the liquid immersion area AR2 areprovided on the dummy substrate DP which is detachable with respect tothe substrate stage PST. However, the temperature sensors 90 may bedirectly provided at predetermined positions of the substrate stage PST.Alternatively, the temperature sensors 90 may be provided detachablywith respect to predetermined positions of the substrate stage PST.Further alternatively, the temperature sensors 90 may be providedmovably in a predetermined area on the substrate stage PST. Furtheralternatively, a temperature sensor for detecting the liquid temperatureof the liquid immersion area AR2 may be provided in the vicinity of theoptical element 2 disposed at the end portion of the projection opticalsystem PL. In the respective embodiments described above, thetemperature of the liquid to be supplied from the respective supplyports is adjusted principally in order to adjust the projection state.However, the temperature of the liquid to be supplied from therespective supply ports may be adjusted for any other purpose. Forexample, the temperature of the liquid to be supplied from therespective supply ports can be adjusted so that the desired temperaturedistribution is obtained on the substrate P.

As described above, pure water is used as the liquid 1 in the foregoingembodiments. Pure water is advantageous in that pure water is availablein a large amount with ease, for example, in the semiconductorproduction factory, and pure water exerts no harmful influence, forexample, on the optical element (lens) and the photoresist on thesubstrate P. Further, pure water exerts no harmful influence on theenvironment, and the content of impurity is extremely low. Therefore, itis also expected to obtain the function to wash the surface of thesubstrate P and the surface of the optical element provided at the endsurface of the projection optical system PL.

It is approved that the refractive index n of pure water (water) withrespect to the exposure light beam EL having a wavelength of about 193nm is approximately in an extent of 1.44. When the ArF excimer laserbeam (wavelength: 193 nm) is used as the light source of the exposurelight beam EL, then the wavelength is shortened on the substrate P by1/n, i.e., to about 134 nm, and a high resolution is obtained. Further,the depth of focus is magnified about n times, i.e., about 1.44 times ascompared with the value obtained in the air. Therefore, when it isenough to secure an approximately equivalent depth of focus as comparedwith the case of the use in the air, it is possible to further increasethe numerical aperture of the projection optical system PL. Also in thisviewpoint, the resolution is improved.

In the embodiment of the present invention, the optical element 2 isattached to the end portion of the projection optical system PL. Thelens can be used to adjust the optical characteristics of the projectionoptical system PL, including, for example, the aberration (for example,spherical aberration and comatic aberration). The optical element, whichis attached to the end portion of the projection optical system PL, maybe an optical plate usable to adjust the optical characteristic of theprojection optical system PL. Alternatively, the optical element may bea plane parallel plate through which the exposure light beam EL istransmissive. When the optical element to make contact with the liquid 1is the plane parallel plate which is cheaper than the lens, it is enoughthat the plane parallel plate is merely exchanged immediately beforesupplying the liquid 1 even when any substance (for example, anysilicon-based organic matter), which deteriorates the transmittance ofthe projection optical system PL, the illuminance of the exposure lightbeam EL on the substrate P, and the uniformity of the illuminancedistribution, is adhered to the plane parallel plate, for example,during the transport, the assembling, and/or the adjustment of theexposure apparatus EX. An advantage is obtained such that the exchangecost is lowered as compared with the case in which the optical elementto make contact with the liquid 1 is the lens. That is, the surface ofthe optical element to make contact with the liquid 1 is dirtied, forexample, due to the adhesion of scattered particles generated from theresist by being irradiated with the exposure light beam EL or anyadhered impurity contained in the liquid 1. Therefore, it is necessaryto periodically exchange the optical element. However, when the opticalelement is the cheap plane parallel plate, then the cost of the exchangepart is low as compared with the lens, and it is possible to shorten thetime required for the exchange. Thus, it is possible to suppress theincrease in the maintenance cost (running cost) and the decrease in thethroughput.

When the pressure, which is generated by the flow of the liquid 1, islarge between the substrate P and the optical element disposed at theend portion of the projection optical system PL, it is also allowablethat the optical element is tightly fixed so that the optical element isnot moved by the pressure, rather than allowing the optical element tobe exchangeable.

The embodiment of the present invention is constructed such that thespace between the projection optical system PL and the surface of thesubstrate P is filled with the liquid 1. However, for example, anotherarrangement may be adopted such that the space is filled with the liquid1 in a state in which a cover glass constructed of a plane parallelplate is attached to the surface of the substrate P.

The liquid 1 is water in the embodiment of the present invention.However, the liquid 1 may be any liquid other than water. For example,when the light source of the exposure light beam EL is the F₂ laser, theF₂ laser beam is not transmitted through water. Therefore, in this case,those preferably usable as the liquid 1 may include, for example, afluorine-based fluid such as fluorine-based oil through which the F₂laser beam is transmissive. Alternatively, other than the above, it isalso possible to use, as the liquid 1, those (for example, cedar oil)which have the transmittance with respect to the exposure light beam EL,which have the refractive index as high as possible, and which arestable against the photoresist coated on the surface of the substrate Pand the projection optical system PL. Also in this case, the surfacetreatment is performed depending on the polarity of the liquid 1 to beused.

The substrate P, which is usable in the respective embodiments describedabove, is not limited to the semiconductor wafer for producing thesemiconductor device. Those applicable include, for example, the glasssubstrate for the display device, the ceramic wafer for the thin filmmagnetic head, and the master plate (synthetic quartz, silicon wafer)for the mask or the reticle to be used for the exposure apparatus.

As for the exposure apparatus EX, the present invention is alsoapplicable to the scanning type exposure apparatus (scanning stepper)based on the step-and-scan system for performing the scanning exposurefor the pattern of the mask M by synchronously moving the mask M and thesubstrate P as well as the projection exposure apparatus (stepper) basedon the step-and-repeat system for performing the full field exposure forthe pattern of the mask M in a state in which the mask M and thesubstrate P are allowed to stand still, while successively step-movingthe substrate P. The present invention is also applicable to theexposure apparatus based on the step-and-stitch system in which at leasttwo patterns are partially overlaid and transferred on the substrate P.

The present invention is also applicable to a twin-stage type exposureapparatus. The structure and the exposure operation of the twin-stagetype exposure apparatus are disclosed, for example, in Japanese PatentApplication Laid-open Nos. 10-163099 and 10-214783 (corresponding toU.S. Pat. Nos. 6,341,007, 6,400,441, 6,549,269, and 6,590,634),Published Japanese Translation of PCT International Publication forPatent Application No. 2000-505958 (corresponding to U.S. Pat. No.5,969,441), and U.S. Pat. No. 6,208,407, contents of which areincorporated herein by reference within a range of permission of thedomestic laws and ordinances of the state designated or selected in thisinternational application.

As for the type of the exposure apparatus EX, the present invention isnot limited to the exposure apparatus for the semiconductor deviceproduction apparatus for exposing the substrate P with the semiconductordevice pattern. The present invention is also widely applicable, forexample, to the exposure apparatus for producing the liquid crystaldisplay device or for producing the display as well as the exposureapparatus for producing, for example, the thin film magnetic head, theimage pickup device (CCD), the reticle, or the mask.

When the linear motor is used for the substrate stage PST and/or themask stage MST, it is allowable to use any one of those of the airfloating type based on the use of the air bearing and those of themagnetic floating type based on the use of the Lorentz's force or thereactance force. Each of the stages PST, MST may be either of the typein which the movement is effected along the guide or of the guidelesstype in which no guide is provided. An example of the use of the linearmotor for the stage is disclosed in U.S. Pat. Nos. 5,623,853 and5,528,118, contents of which are incorporated herein by reference withina range of permission of the domestic laws and ordinances of the statedesignated or selected in this international application.

As for the driving mechanism for each of the stages PST, MST, it is alsoallowable to use a plane motor in which a magnet unit provided withtwo-dimensionally arranged magnets and an armature unit provided withtwo-dimensionally arranged coils are opposed to one another, and each ofthe stages PST, MST is driven by the electromagnetic force. In thisarrangement, any one of the magnet unit and the armature unit isconnected to the stage PST, MST, and the other of the magnet unit andthe armature unit is provided on the side of the movable surface of thestage PST, MST.

The reaction force, which is generated in accordance with the movementof the substrate stage PST, may be mechanically released to the floor(ground) by using a frame member so that the reaction force is nottransmitted to the projection optical system PL. The method for handlingthe reaction force is disclosed in detail, for example, in U.S. Pat. No.5,528,118 (Japanese Patent Application Laid-open No. 8-166475), contentsof which are incorporated herein by reference within a range ofpermission of the domestic laws and ordinances of the state designatedor selected in this international application.

The reaction force, which is generated in accordance with the movementof the mask stage MST, may be mechanically released to the floor(ground) by using a frame member so that the reaction force is nottransmitted to the projection optical system PL. The method for handlingthe reaction force is disclosed in detail, for example, in U.S. Pat. No.5,874,820 (Japanese Patent Application Laid-open No. 8-330224), contentsof which are incorporated herein by reference within a range ofpermission of the domestic laws and ordinances of the state designatedor selected in this international application.

As described above, the exposure apparatus EX according to theembodiment of the present invention is produced by assembling thevarious subsystems including the respective constitutive elements asdefined in claims so that the predetermined mechanical accuracy, theelectric accuracy, and the optical accuracy are maintained. In order tosecure the various accuracies, those performed before and after theassembling include the adjustment for achieving the optical accuracy forthe various optical systems, the adjustment for achieving the mechanicalaccuracy for the various mechanical systems, and the adjustment forachieving the electric accuracy for the various electric systems. Thesteps of assembling the various subsystems into the exposure apparatusinclude, for example, the mechanical connection, the wiring connectionof the electric circuits, and the piping connection of the air pressurecircuits in correlation with the various subsystems. It goes withoutsaying that the steps of assembling the respective individual subsystemsare performed before performing the steps of assembling the varioussubsystems into the exposure apparatus. When the steps of assembling thevarious subsystems into the exposure apparatus are completed, theoverall adjustment is performed to secure the various accuracies as theentire exposure apparatus. It is desirable that the exposure apparatusis produced in a clean room in which, for example, the temperature andthe cleanness are managed.

As shown in FIG. 16, the microdevice such as the semiconductor device isproduced by performing, for example, a step 201 of designing thefunction and the performance of the microdevice, a step 202 ofmanufacturing a mask (reticle) based on the designing step, a step 203of producing a substrate as a base material for the device, an exposureprocess step 204 of exposing the substrate with a pattern of the mask byusing the exposure apparatus EX of the embodiment described above, astep 205 of assembling the device (including a dicing step, a bondingstep, and a packaging step), and an inspection step 206.

According to the present invention, even when the temperaturedistribution arises in the liquid for forming the liquid immersion areadue to the distribution of the exposure light beam or the distributionof the pattern, the pattern can be transferred onto the substrate in thedesired state by adjusting the projection state of the pattern image onthe basis of the distribution of the exposure light beam or thedistribution of the pattern. Accordingly, it is possible to produce thehigh performance device. Further, the temperature of the liquid forforming the liquid immersion area is directly measured by thetemperature sensors arranged in the vicinity of the image plane of theprojection optical system, and thus the liquid for forming the liquidimmersion area can be adjusted to be in the desired temperature state onthe basis of the result of the measurement. Therefore, the pattern canbe transferred onto the substrate in the desired state.

What is claimed is:
 1. An exposure apparatus which exposes a substrateby projecting an image of a pattern onto the substrate through a liquid,the exposure apparatus comprising: a projection optical system whichprojects the image of the pattern onto the substrate; a recovery portwhich recovers the liquid supplied onto the substrate; and a temperaturesensor which measures a temperature of the liquid recovered via therecovery port.
 2. The exposure apparatus according to claim 1, furthercomprising a recovery tube which is connected to the recovery port andin which the temperature sensor is arranged.
 3. The exposure apparatusaccording to claim 1, further comprising a supply port which suppliesthe liquid onto the substrate, wherein a temperature of the liquid to besupplied from the supply port is adjusted on the basis of a result of ameasurement performed by the temperature sensor.
 4. The exposureapparatus according to claim 1, further comprising a supply port whichsupplies the liquid onto the substrate, wherein a supply amount of theliquid supplied from the supply port per a unit of time is adjusted onthe basis of a result of a measurement performed by the temperaturesensor.
 5. The exposure apparatus according to claim 1, wherein aprojection state of the projection optical system is adjusted on thebasis of a result of a measurement performed by the temperature sensor.6. The exposure apparatus according to claim 5, further comprising asubstrate stage which is movable while holding the substrate, whereinthe adjustment of the projection state includes controlling a movementof the substrate stage.
 7. The exposure apparatus according to claim 1wherein the recovery port includes a plurality of recovery ports whichare arranged at positions different from each other, and the suppliedliquid is recovered via the plurality of recovery ports, and thetemperature sensor includes a plurality of sensors which are arrangedcorresponding to the plurality of recovery ports, respectively.
 8. Acontrol method used in an exposure apparatus which exposes a substrateby projecting an image of a pattern onto the substrate through aprojection optical system and a liquid, the control method comprising:recovering the liquid supplied onto the substrate via a recovery port;and measuring a temperature of the recovered liquid using a temperaturesensor.
 9. The control method according to claim 8, wherein thetemperature of the liquid is measured by arranging the temperaturesensor in a recovery tube which is connected to the recovery port. 10.The control method according to claim 8, wherein the liquid is suppliedonto the substrate via a supply port, and a temperature of the liquid tobe supplied from the supply port is adjusted on the basis of a result ofa measurement performed by the temperature sensor.
 11. The controlmethod according to claim 8, wherein the liquid is supplied onto thesubstrate via a supply port, and a supply amount of the liquid suppliedfrom the supply port per a unit of time is adjusted on the basis of aresult of a measurement performed by the temperature sensor.
 12. Thecontrol method according to claim 8, wherein a projection state of theprojection optical system is adjusted on the basis of a result of ameasurement performed by the temperature sensor.
 13. The control methodaccording to claim 12, wherein the adjustment of the projection stateincludes controlling a movement of a substrate stage which is movablewhile holding the substrate.
 14. The control method according to claim8, wherein the recovery port includes a plurality of recovery portswhich are arranged at positions different from each other, and thesupplied liquid is recovered via the plurality of recovery ports, andthe temperature sensor includes a plurality of sensors which arearranged corresponding to the plurality of recovery ports, respectively.15. A device producing method comprising: exposing a substrate using anexposure apparatus as defined in claim 1, the substrate being a basemember of a device; and assembling the device using the exposedsubstrate.